CSET

Demonstrate knowledge of electrostatic and magnetostatic phenomena, including evaluating examples of each type of phenomenon.

ELECTROSTATICS: electric charges at rest - basic characteristics of static electricity: + The effects of static electricity are explained by a physical quantity, called electric charge (unit: coulomb) + There are only two types of charge, one called positive and the other called negative. + Like charges repel, whereas unlike charges attract. + The force between charges decreases with distance. + Every atom is made of negatively-charged electrons surrounding a positively-charged nucleus. The nucleus contains protons, which are positively charged, and neutrons, which are neutral (they have no net electric charge). Electrons can move from one atom, molecule or material, to another. Most objects do not have an electric charge because there is a balance of electrons and protons in the material that makes up the object. In certain circumstances, there can be an imbalance of protons and electrons. An object with a greater number of electrons than protons is negatively charged. An object with more protons than electrons is positively charged. + Charging by Friction: When two materials are rubbed together, some electrons may be transferred from one material to the other, leaving them both with a net electric charge. The material that lost electrons becomes positively charged, while the material that gained electrons becomes negatively charged. Both insulators and conductors can gain a net charge in this way. This is how clothing gets charged in the clothes dryer, or our bodies get charged when we walk across a carpeted floor. - separation of charge in atoms: Charges in atoms and molecules can be separated—for example, by rubbing materials together. + Some atoms and molecules have a greater affinity for electrons than others and will become negatively charged by close contact in rubbing, leaving the other material po

Compare the characteristics of mechanical and electromagnetic waves (e.g., transverse/longitudinal, travel through various media, relative speed).

Wave: a disturbance that travels/propagates from the place it was created - Waves transfer energy from one place to another, but they do not necessarily transfer any mass MECHANICAL WAVES: they require a medium to travel through. The energy is passed from atom to atom, molecule to molecule, through successive collisions of particles in the material - The medium can be a solid, liquid, or gas - The speed of the wave depends on the material properties of the medium though which is it traveling - i.e. sound and water waves - slower than EM waves - pulse wave: a sudden disturbance in which one wave or a few waves are generated - periodic wave: repeats the same oscillation for several cycles - simple harmonic motion: each particle in the medium experiences simple harmonic motion is periodic waves by moving back and forth periodically though the same positions - can be transverse or longitudinal: + transverse: propagates so that the disturbance is perpendicular to the direction of propagation * ripples on the surface of water; vibrations in a guitar string. + longitudinal: the disturbance is parallel to the direction of propagation * sound waves in air and water are longitudinal --> the disturbance is caused by a change in air pressure + surface: medium moves up and down and side to side; hybrid between transverse and longitudinal; ocean waves - earthquakes have both longitudinal and transverse components: + P-waves: longitudinal waves; can travel through solids, liquids, and gases. + S-waves: transverse waves; travel through solids only. + Surface waves: have and up-down and side-to-side motion; slowest ELECTROMAGNETIC WAVES: do not require a material medium to pass through. They are affected by the presence of matter which can slow the waves down as the energy is absorbed, transmitted, reflected by the particles

Apply knowledge of the physical and chemical properties of water.

:- Hydrogen bonding: electromagnetic attraction between polar molecules where hydrogen is bound to a larger atom; attraction between the positive and negative poles of charged atoms (dipole-dipole attraction) + Intermolecular: hydrogen bonding between two different molecules + Intramolecular: hydrogen bonding within the same molecule + Can form between atoms with a partial charge + Since water is a molecule with partially charged atoms, water can form a hydrogen bond with other water molecules - Density: measure of mass of an object per unit volume + The ordered, unbroken hydrogen bonds in ice cause water molecules to be farther apart than they would be in the liquid state. This resulting lowered density of ice relative to water explains why it floats. + Because these hydrogen bonds are all forming at the same time, the water molecules are becoming more ordered; they're forming a crystalline structure. + Because of this linkage, the water molecules are in this rigid structure, and this rigid structure is holding them farther apart than they would be if they had been in the liquid state. Because they are being held farther apart, they're occupying more volume, and because they're occupying more volume - if we remember our density formula, we said density was equal to mass divided by volume - if I've increase the volume but kept the mass the same (because we've increased this volume down here) the overall density has decreased because the denominator has increased but the numerator has stayed the same. So because this density is lower, ice is going to float on water. - States of matter and specific heat: + Water has a high specific heat: The energy that's needed to raise the temperature of one gram of a substance one degree Celsius: the specific heat + water - we also have to remember that water is linked togeth

Analyze how chemical energy in fuel is transformed to heat.

- A fuel is a material that can be burned to produce heat, light or power. - Examples of fuel include wood, coal, natural gas, and oil. The energy stored within them originally came from the sun. It was absorbed by plants, and stored inside them. In the case of wood that's the end of the story: trees that were chopped down contain this energy. But some of the energy did not go into logs of wood. All plants that lived in the past either died or were eaten by animals, and those animals eventually died too. This dead plant and animal material was compressed on the high heat and pressure over millions of years to form things like coal, oil, and gas. The original energy from the sun is stored in these fuels. - When we burn fuels, it begins a process called combustion. Combustion is where you burn a fuel in the presence of an oxidant like oxygen. Heat is produced, because the bonds in the fuel store more energy than the bonds in the water and carbon dioxide that are the products of combustion. - Energy is the capacity for doing work or supplying heat. When you fill your car with gasoline, you are providing it with potential energy. Chemical potential energy is the energy stored in the chemical bonds of a substance. The various chemicals that make up gasoline contain a large amount of chemical potential energy that is released when the gasoline is burned in a controlled way in the engine of the car. + The release of that energy does two things. Some of the potential energy is transformed into work, which is used to move the car. At the same time, some of the potential energy is converted to heat, making the car's engine very hot. The energy changes of a system occur as either heat or work, or some combination of both. - Due to the absorption of energy when chemical bonds are broken, and the release of energy when chemical

Demonstrate knowledge of how lenses are used in simple optical systems, including the camera, telescope, microscope, and eye.

- A lens is an instrument that refracts (or bends) light in such a way as to allow the user to see the world around them in a different way. A lens is a piece of glass (or plastic or other material) that has been carefully shaped so that the way it refracts light forms an image. - A simple lens is a basic device that uses a single lens to refract light. The most obvious example of a simple lens is a magnifying glass, which uses a single lens to magnify an object - A compound lens uses multiple lenses. An example of a compound lens is a compound microscope, which uses multiple lenses to increase the viewer's capacity to magnify an object. - Concave lenses are thinnest in the middle and widest at the edges, as if the face of the lens were 'caving' in on itself. This shape results in spreading the light into a wider arc. + From the diagram, it's clear that the lens causes rays of light to diverge, or spread apart, as they pass through it. Note that the image formed by a concave lens is on the same side of the lens as the object. It is also smaller than the object and right-side up. However, it isn't a real image. It is a virtual image. Your brain "tricks" you into seeing an image there. The light rays actually pass through the glass to the other side and spread out in all directions. - Convex lenses, on the other hand, are thickest in the middle and thinnest at the edges, thus focusing light on a central point. Most lenses that we commonly think of (like in microscopes, cameras, the human eye, and telescopes, a magnifying glass) are convex. + A convex lens causes rays of light to converge, or meet, at a point called the focus (F). A convex lens forms either a real or virtual image. It depends on how close the object is to the lens relative to the focus. * if the object is closer to the lens than the focus is, a virtu

Analyze chemical bonding with respect to an element's position in the periodic table.

- As you move across a period in the periodic table, the types of commonly encountered bonding interactions change. For example, at the beginning of Period 2, elements such as lithium and beryllium form only ionic bonds, in general. Moving across the period, elements such as boron, carbon, nitrogen and oxygen tend to form covalent bonds. Fluorine can form ionic bonds with some elements, such as carbon and boron, and neon does not tend to form any bonds at all. - The left-most elements form more ionic bonds, and the further-right elements tend to form more covalent bonds. - Metals give away their valence electrons when bonding, whereas non-metals tend to take electrons. **think about the valence electrons IONIC bonds form between a metal and a nonmetal. + Ionic bonds are bonds formed between ions with opposite charges. When one atom loses an electron and another atom gains that electron, the process is called electron transfer + In an ionic bond, one atom donates an electron to another atom. This stabilizes both atoms. Because one atom essentially gains an electron and the other loses it, an ionic bond is polar. In other words, one atom in the bond has a positive charge, while the other has a negative charge. + Often, these atoms dissociate into their ions in water. + Atoms that participate in ionic bonding have different electronegativity values from each other. + Examples of compounds with ionic bonds include salt, such as table salt (NaCl). In salt, the sodium atom donates its electron, so it yields the Na+ ion in water, while the chlorine atom gains an electron and becomes the Cl- ion in water. + Metals are the elements on the left side of the Periodic Table. The most metallic elements are Cesium and Francium. Metals tend to lose electrons to attain Noble Gas electron configuration. Groups 1 and 2 (the act

Apply knowledge of heat transfer by conduction, convection, and radiation, including analyzing examples of each mode of heat transfer.

- CONDUCTION: Conduction is heat transfer through stationary matter by physical contact. (The matter is stationary on a macroscopic scale—we know there is thermal motion of the atoms and molecules at any temperature above absolute zero.) Heat transferred between the electric burner of a stove and the bottom of a pan is transferred by conduction. + Heat conduction occurs by transfer of vibrational energy between molecules, or movement of free electrons. Conduction is particularly important with metals and occurs without observable movement of matter. + On a microscopic scale, conduction occurs as rapidly moving or vibrating atoms and molecules interact with neighboring particles, transferring some of their kinetic energy. + Conduction is the most significant form of heat transfer within a solid object or between solids in thermal contact. + Conduction is most significant in solids, and less though in liquids and gases, due to the space between molecules. Fluids and gases are less conductive than solids. This is due to the large distance between atoms in a fluid or (especially) a gas: fewer collisions between atoms means less conduction. + The rate of heat transfer by conduction is dependent on the temperature difference, the size of the area in contact, the thickness of the material, and the thermal properties of the material(s) in contact. + thermal conductivity: the measure of a material's ability to conduct heat * Some materials conduct thermal energy faster than others. For example, the pillow in your room may the same temperature as the metal doorknob, but the doorknob feels cooler to the touch. In general, good conductors of electricity (metals like copper, aluminum, gold, and silver) are also good heat conductors, whereas insulators of electricity (wood, plastic, and rubber) are poor heat conductors. +

Recognize that chemical reactions can be understood in terms of the collisions between ions, atoms, or molecules and the rearrangement of particles.

- Collision theory: describes the mechanism by which chemical reactions occur + In order for an atom or molecule to react with another atom or molecule, they must collide with each other + The collision must be strong enough to break the intramolecular bonds (bonds within a molecule) in the reactants (e.g., the covalent bonds) so that the reaction can occur and new products be formed + Collision theory states that the number of successful or effective collisions is related to the reaction rate. The more successful collisions, the faster the reaction rate. - The collision theory provides us with the ability to predict what conditions are necessary for a successful reaction to take place. These conditions include: + The particles must collide with each other. + The particles must collide with sufficient energy to break the old bonds. --> The amount of energy that reactant particles must have in order to break the old bonds for a reaction to occur is called the activation energy (Ea) + The particles must have proper orientation. - A chemical reaction involves breaking bonds in the reactants, rearranging the atoms into new groupings (the products), and forming new bonds in the products. - The rate, or speed, at which a reaction occurs depends on the frequency of successful collisions. Remember, a successful collision occurs when two reactants collide with enough energy and with the right orientation. That means if there is an increase in the number of collisions, an increase in the number of particles that have enough energy to react, and/or an increase in the number of particles with the correct orientation, the rate of reaction will increase. - The rate of reaction was discussed in terms of three factors: collision frequency, the collision energy, and the geometric orientation. Remember that the collision frequency

Apply knowledge of the principles of conservation of matter to chemical reactions, including balancing chemical equations.

- Conservation of matter: It states that in any given system that is closed to the transfer of matter (in and out), the amount of matter in the system stays constant. A concise way of expressing this law is to say that the amount of matter in a system is conserved. - In any chemical change, one or more initial substances change into a different substance or substances. Both the initial and final substances are composed of atoms because all matter is composed of atoms. According to the law of conservation of matter, matter is neither created nor destroyed, so we must have the same number and type of atoms after the chemical change as were present before the chemical change. - The MASS of the reactants must equal the MASS of the products. - The principles of stoichiometry are based upon the law of conservation of mass. Matter can neither be created nor destroyed, so the mass of every element present in the product(s) of a chemical reaction must be equal to the mass of each and every element present in the reactant(s). - Stoichiometry is a branch of chemistry that deals with the relative quantities of reactants and products that are consumed/produced within a given chemical reaction. In order to make any stoichiometric determinations, however, we must first look to a balanced chemical equation. In a balanced chemical equation, we can easily determine the stoichiometric ratio between the number of moles of reactants and the number of moles of products, because this ratio will always be a positive integer ratio. - In a balanced reaction, both sides of the equation have the same number of elements. The stoichiometric coefficient is the number written in front of atoms, ion and molecules in a chemical reaction to balance the number of each element on both the reactant and product sides of the equation.

Apply knowledge of the development and organization of the periodic table and predict the properties of elements on the basis of their positions in the periodic table.

- Dmitri Mendeleev: table ordering the elements by their atomic number (number of protons) - Columns: groups (have similar properties) - Rows: periods o Alkali metals (group 1): soft, silvery, react violently with water to form a basic/alkaline solution o Alkaline earth metals (group 2): shiny, silvery white o Halogens (group 17): very reactive and poisonous, commonly found in bleach/disinfectants o Noble gases (group 18): colorless, odorless, unreactive; found in lightbulbs - nonmetals: halogens, hydrogen, and nonmetals o Metals: shiny, good conductors of heat and electricity, malleable, ductile - alkali and alkaline earth metals - transition metals (group 3-12) - basic metals: under staircase in groups 13-16 o Nonmetals: brittle in solid form, dull, poor conductors of heat and electricity, lower melting and boiling points than metals (gases at room temp usually). above staircase: C, N, O, F, P, S, Cl, Se, Br, I o Metalloids: found on the staircase; have properties of metals and nonmetals (B, Si, Ge, As, Sb, Te, At) o Lanthanoids: continuation of row 6 o actinoids: continuation of row 7 TRENDS: the trends are a result of (1) the charge inside the nucleus and (2) the number of electrons in the valence shell; (3) shielding: as the number of electron shells increases, they have the effect of shielding the attractive charge from the nucleus and reducing the electrostatic attraction between the positive protons and negative electrons ATOMIC RADIUS: the distance from the nucleus to the edge of the electron cloud or half the distance between two identical atoms' nuclei in a covalent bond + As you move from top to bottom in the same group, the atomic radius with INCREASE because new energy levels are needed to hold the electrons, resulting in a larger atom + As you move from left to right in the same period, the atomi

Demonstrate knowledge of kinetic and potential energy.

- Energy: the ability to do work + Scalar: no direction and is described by magnitude alone - All energy in the universe falls into two main types: kinetic and potential. + Kinetic energy is the energy of motion. Any object in motion has kinetic energy and is using kinetic energy every moment it is moving. Kinetic energy can vary in quantity depending on the mass of an object and how fast it is moving. Therefore mass and speed factor into the kinetic energy of an object. ** Objects with less mass have less kinetic energy than objects with more mass moving at the same speed. Ek or KE = ½ mv2 where E is energy (J or Nm), m is mass (kg) and v is speed (m/s) - Work is the change in KE of a system: Wnet = Δ Ek - The energy associated with an object's motion is called kinetic energy. A speeding bullet, a walking person, and electromagnetic radiation like light all have kinetic energy. Another example of kinetic energy is the energy associated with the constant, random bouncing of atoms or molecules. This is also called thermal energy - the greater the thermal energy, the greater the kinetic energy of atomic motion, and vice versa. The average thermal energy of a group of molecules is what we call temperature, and when thermal energy is being transferred between two objects, it's known as heat. + Potential energy is energy an object has due to its position or arrangement. It is present when an object's position results in the storage of energy that can be used at some point in the future. Positions that result in potential energy storage include objects located at heights above ground level, stretched positions of elastic objects, and configurations of charged objects that generate an expected response when they interact. These are referred to as gravitational potential energy, elastic potential energy, and electr

Demonstrate knowledge of how the transfer of energy as heat is related to changes in temperature and interpret the direction of heat flow in a system.

- First law of thermodynamics (specific version of law of conservation of energy): applied to systems where heat transfer and work are the means by which energy is transferred into and out of a system. It states that any change in the energy of a system (ΔU) is equal to the net transfer of heat from or to the system (Q) plus the net work done on or by the system (W) ΔU = Q -W + Value for W is negative because work is being done BY the system, moving energy OUT of the system + Value for W is positive when work is being done TO the system (ΔU = Q + W) - Second law of thermodynamics: entropy always increases over time; order tends to disorder + Entropy: a measure of how much the energy is spread out in a system. The energy is not available to do work. Entropy in the universe NEVER decreases, it will eventually increase to a point where all energy is evenly dispersed (maximum entropy) + Entropy can be reduced in a closed system, but always by increasing entropy in the wider universe - zeroth law of thermodynamics says that no heat is transferred between two objects in thermal equilibrium; therefore, they are the same temperature. - temperature: a measure of the average kinetic energy of the atoms or molecules in a system. + when a system absorbs or loses heat, the average kinetic energy of the molecules will change. Thus, heat transfer results in a change in the system's temperature as long as the system in not undergoing a phase change. - we can calculate the heat released or absorbed using the specific heat capacity, C, the mass of the substance m, and the change in temperature ΔT using the equation: q = m x C x ΔT + q or Q is Heat (unit: joules); heat is thermal energy transferred between two systems at different temperatures that come into contact (thermal energy is transferred from a hotter system to

Demonstrate knowledge of the characteristics of the different states of matter.

- matter: anything that has mass and takes up space - gas: a form of matter that does not have a definite volume or shape; has a low density and can diffuse easily - liquid: has a definite volume but not a definite shape. Molecules are more tightly packed but can still move and flow past each other. Able to diffuse and ix with other liquids, but slower mixing than gases. Surface tension: the force of attraction that keeps molecules on the surface of a liquid together. - solid: definite volume and shape. Tightly packed molecules that have limited movement and are incompressible and hold their volume and shape. Typically the densest state of matter (not in water); diffuse slowly and not well - plasma: a gas that has gotten so hot that negatively charged free electrons and positively charged ions exist together in it; these free electrons mean that plasma easily conducts energy. Neither a definite volume nor shape.

Apply knowledge of Newton's laws of motion and law of universal gravitation and recognize the relationship between these laws and the laws of conservation of energy and momentum.

- Force: a push, pull, or twist acting on an object that can cause objects to move, speed up, slow down, change direction, change shape - Measured in Newtons: kg m/s2 - Newton's first law (law of inertia): an object at rest stays at rest and an object in motion stays in motion (same speed and direction - velocity) unless acted upon by an unbalanced force; describes an object's resistance to change + Only an unbalanced force will cause an object to accelerate by changing its speed, direction, or both speed and direction + Static equilibrium: objects at rest + Dynamic equilibrium: object in motion with a constant velocity + Inertia: the natural tendency of an object to resist changes in its state of motion - Newton's second law: the amount of acceleration is directly proportional to the net force acting on the object; F = ma + Net force: the sum of all forces acting on an object in a particular direction + Applies to the behavior of objects for which all existing forces are not balanced and states the acceleration of an object is dependent upon the net force acting upon the object and the mass of the object + Acceleration of the object is directly proportional to the net force applied to it and inversely proportional to the mass of the object: the greater the force applied, the greater the acceleration and the more massive the object, the slower the acceleration + Mass: measures the amount of matter (atoms) making up an object (kg) * Vs weight: the measurement of the pull of gravity on an object, so it is also called the force due to gravity (N) --> Weight = mg. On earth: F=ma --> (70 kg)(9.8 m/s2) = 686 N + Centripetal acceleration: an object traveling at constant speed in a circular path experiences acceleration because the direction of velocity is always changing. Acceleration is in the direction of the ch

Demonstrate knowledge of the principle of conservation of energy, including analyzing energy transfers.

- Law of conservation of energy (1st law of thermodynamics): energy cannot be created or destroyed but it can be changed from one form to another and transferred from one system to another W = E(initial) - E(final) - Mechanical energy (Ep + Ek) of a system is constant --> any change in Ep is equal and opposite to any change in Ek --> Etotal = Ep + Ek --> KEi+PEi=KEf+PEf - When work is done, the energy of the system changes. If work is done on the system, energy is added. If the system does work on the environment, energy goes out of the system - In systems, energy is not perfectly conserved. Energy is always being lost to the environment, often due to frictional components - example: consider a golfer on the moon - gravitational acceleration 1.625 m/s2 - striking a golf ball. the ball leaves the club at an angle of 45 degrees to the lunar surface traveling at 20 m/s both horizontally and vertically - total velocity 28.28 m/s. How high would the golf ball go? + E (mechanical) = 1/2mv^2 + mgh + apply conservation of energy: 1/2 mv^2 (initial) = mgh + 1/2mv^2 (final) + solve for h: h = (1/2 (vi^2 - vf^2))/g = (1/2 (28.28^2 -20^2)/1.625 = 123 m + how did we know the final speed was 20 m/s? at the peak height, the vertical component of the velocity becomes zero, so the only velocity component at peak height is the horizontal component which doesn't change during the flight and is 20 m/s. - even though energy is conserved in an energy conversion process, the output of useful energy or work will be less than the energy input. the efficiency of an energy conversion process is: efficiency = useful energy or work output/ total energy input = W(out)/E(in)

Describe the effect of temperature, pressure, and concentration on chemical equilibrium (Le Chatelier's principle) and reaction rate.

- Le Châtelier's principle: When a system at equilibrium is subjected to change (e.g., in temperature, pressure, concentration, or volume) the system changes to a new equilibrium and this change partially counteracts the change applied to the system - An external stress can change the system, and the system reacts in a way that reduced or opposes the change as much as possible CONCENTRATION: A + 2B <----> C + D : the position of the equilibrium moves to the right if you increase the volume of A A + 2B <----> C + D : the position of the equilibrium moves to the left if you decrease the concentration of A PRESSURE: Pressure is caused by gas molecules hitting the sides of their container. The more molecules you have in the container, the higher the pressure will be. The system can reduce the pressure by reacting in such a way as to produce fewer molecules. A + 2B <----> C + D : the position of equilibrium moves to right if you increase the pressure on the reaction + Increased pressure: In this case, there are 3 molecules on the left-hand side of the equation, but only 2 on the right. By forming more C and D, the system causes the pressure to reduce. Increasing the pressure on a gas reaction shifts the position of equilibrium towards the side with fewer molecules. A + 2B <----> C + D : The position of equilibrium moves to the left if you decrease the pressure on the reaction + Decreased pressure: The equilibrium will move in such a way that the pressure increases again. It can do that by producing more molecules. In this case, the position of equilibrium will move towards the left-hand side of the reaction. Decreasing the pressure on a gas reaction shifts the position of equilibrium towards the side with more molecules. TEMPERATURE: If we picture heat as a reactant or a product, we can apply Le Chatelier's princip

Demonstrate knowledge of the definition of pressure and how pressure relates to fluid flow and buoyancy, including describing everyday phenomena (e.g., the functioning of heart valves, atmospheric pressure).

- Pressure: force per unit area; p = F/A + Units: Pascal (N/m2), psi, atm, mmHg + Pressure only concerns the force component perpendicular to the surface upon which it acts + Pressure of an ideal gas: P = nRT/V, where n is the number of gas molecules, R is the ideal gas constant (R = 8.314 J mol-1 K-1), T is the temperature of the gas, and V is the volume of the container - the pressure exerted by the gas can be increased by: ** increasing the number of collisions of gas molecules per unit time by increasing the number of gas molecules ** increasing the KE of the gas by increasing the temperature ** decreasing the volume pf the container - Fluids: fluid is defined as any substance that flows and that takes the shape of its container (gas and liquids) + When force is exerted on a fluid, pressure pushes on the walls of the surrounding container and on all parts of the fluid itself + Pressure in liquids increase with depth due to gravity * The liquid at the bottom has to bear the weight (force due to gravity) of the liquid above it and the air above that + Hydrostatic pressure: the pressure exerted by a fluid at equilibrium at a given point within the fluid due to the force of gravity; it increases in proportion to depth measured form the surface because of the increasing weight of fluid exerting downward force above, assuming the fluid is incompressible and at rest : P = ρgh or P = ρgd, where P is fluid pressure, ρ is fluid density, g is acceleration due to gravity and h (or d) is fluid depth - Buoyant force: the upward force of a fluid + When an object is submerged in water, the pressure on the bottom of the object is greater than on the top creating a net upward force on the object, so the object is buoyed upward against gravity + Archimedes' principle: the buoyant force is equal to the weight of the

Analyze displacement, motion, and forces using models (e.g., vector, graphic representation, equations).

- Scalar: quantities with magnitude + Distance: total distance covered during an object's motion (m) ** Change in distance (Δd) = speed (v) x change in time (Δt) + Speed: the rate at which an object covers a certain distance (m/s) ** Instantaneous speed: the speed at a given time ** Average speed: total distance traveled over the entire time interval - Vector: quantities with magnitude and direction + Displacement: overall change in position of an object ** Displacement (Δx) = velocity (v) x change in time (Δt) + Velocity: an object's speed and direction (m/s in direction) ** Velocity = displacement/time à (v) = (Δx)/(Δt) + Acceleration: occurs when velocity changes; can be changed by altering speed or direction (or both) ** Acceleration (a) = (Δv)/(Δt); or change in velocity/change in time - Positive acceleration: acts in the direction of an object's movement - Negative acceleration: acts in the direction opposite to the object's movement; The object will slow down, eventually stop, eventually travel backwards Equations: (Δx) = (v) x (Δt) (v) = (Δx)/(Δt) (a) = (Δv)/(Δt) Displacement and velocity with constant acceleration: vf = vi + aΔt Δx = ½ (vi + vf)Δt a = (vi + vf)/Δt Δx = vf Δt - ½ aΔt2 · xf = xi + vit + ½ at2 vf2 = vi2 + 2ad d = (t (vi + vf))/2 vector: · Step 1: Find the coordinates of your two displacement vectors · Step 2: Move the second displacement vector so it starts where the first displacement vector ended · Step 3: Draw a new vector that is the addition of the two displacement vectors · Step 4: Find the coordinates of the new displacement vector · Find the resultant vector of the vector A (5, -4) and vector B (-3, -2). o Since you are given the coordinates directly, you can go ahead and add the points together following the formula: o (x1 + x2, y1 + y2) à

Demonstrate knowledge of how energy and information are transferred by waves without mass transfer, including recognizing technology that employ this phenomenon.

- This is because waves transfer energy and not mass. For example, a wave in the ocean doesn't transfer water particles from one place to another, but rather those particles are just moving up and down perpendicular to, or at a right angle to, the movement of the horizontal wave. This happens as energy is transformed from potential or 'stored' energy to kinetic or 'movement' energy, and then back to potential energy again. - energy is transferred through the vibrations of the medium's particles. So a water wave transfers energy through the vibration of the water particles, sound waves travel through the vibration of air particles or the particles of a liquid or solid, and electromagnetic and magnetic fields vibrate to transfer energy through electromagnetic waves. - not all waves are the same size, shape, or speed. So as frequency increases (meaning more waves are produced), the wavelength decreases. And as frequency decreases (fewer waves are produced) the wavelength increases. - radio waves: radio waves have a much lower frequency and longer wavelength, meaning they have less energy. + MRI uses magnetic fields and radio waves to measures how much water is in different tissues of the body, maps the location of the water and then uses this information to generate a detailed image. + Radio receivers detect radio waves and transform them into sounds we can hear. each radio transmitting station broadcasts a radio wave with a unique frequency called the carrier wave. When there is an audio signal (human/music) to be sent out, that signal is using the transmitting equipment to modify the carrier wave slightly (modulation) ** AM (amplitude modulation): the amplitude of the carrier wave is changed. AM wavelengths are much longer than FM wavelengths, so they are less affected by structures like buildings/mountains so they

Demonstrate knowledge of nuclear forces that hold nuclei together and are responsible for nuclear processes (e.g., fission, fusion) and radioactivity (e.g., alpha, beta, and gamma decay).

- a nuclear reaction that changes the nucleus of an atom: the number of protons and/or neutrons is changed as a result of a nuclear reaction; nuclear reactions RELEASE energy + Albert Einstein's E = mc2 equation relates mass and energy: any reaction produces or consumes energy due to a loss or gain in mass. A small change in mass results in a large change in energy + nuclear binding energy: the amount of energy needed to break one mole of nuclei into individual nucleons. The larger the binding energy per nucleon, the stronger the nucleons are held together, the more stable the nucleus is and the harder it is to break it apart. * light nuclei gain stability by undergoing nuclear fusion. Heavy nuclei gain stability by undergoing nuclear fission. Mass number 60 is most stable, so atoms with mass number greater than 60 tend to fragment into smaller atoms to increase their stability - 2 types of nuclear reactions: FISSION and FUSION + nuclear fission: large nuclei are split into smaller fragments, and neutrons and energy are released; a type of radioactive decay. The total mass is reduced and the "lost" mass appears as an equivalent release of energy * nuclear power plants use nuclear fission to generate power. The nuclei of uranium atoms can undergo nuclear fission naturally. Nuclear power plants use U-235 nucleus to undergo fission by hitting them with neutrons. Ba-141 and Kyrpton-92 are just some of the isotopes that can come from the fission of a U-235 nuclear. Nuclear power plants used controlled chain reactions to generate electrical energy; uses rods to keep chain reaction going and under control * nuclear chain reaction: a continuous series of nuclear fission reactions, a self-sustaining process in which one reaction initiates the next. The number of fissions and the amount of energy released can increase rapi

Analyze the basic substructure of an atom (i.e., protons, neutrons, and electrons).

- atom: the basic unit of an element that carry out chemical reactions. each element is made up of only one type of atom - two elementary particles: electron and quark + quarks make up protons and neutrons (nucleons) + protons have 2 up quarks and 1 down quark; neutrons have 2 down quarks and 1 up quark - strong nuclear force holds quarks together to form protons and neutrons and counteracts the tendency of the positively-charged protons to repel each other - atoms are made up of 3 components and have precise structure. Change it in any way and the behavior or even the type of atom changes. - Neutral atoms: contain the same number of protons as electrons - The electrons (negative charge, negligible mass) in the outer shell determine an atom's behavior during a chemical reaction/chemical behavior of an atom - The number of protons (positively charged, same mass as neutrons) determines the element; The number of protons in the nucleus is called the atomic number (Z) - The number of protons and neutrons (neutral; same mass as proton) together is the mass number (A) - Atomic mass is based on the average atomic masses of its isotopes and the abundance of each isotope; Number of neutrons = atomic mass - atomic number - Adding more electrons produces more orbitals. The orbitals have different shapes. Orbital: the orbit that electrons can take around the nucleus - Valence shell: the electrons in the outer shell that take part in a chemical reaction + Electrons with full valence shells are chemically stable; they don't undergo chemical reactions. An atom without a full valence shell will undergo a chemical reaction in order to obtain a full valence shell + During the reaction, electrons may be gained or lost, or shared between atoms depending on the number of electrons in the valence shell + Octet rule: atoms like to have

Interpret simple series and parallel circuits.

- circuit: a path that electrons can flow through - series circuit: provides only one path for the electrons to get through the resistive part of the circuit + the total resistance of a series circuit is equal to the sum of all the individual resistances; adding a resistor will always cause the total resistance to increase. ADD RESISTANCES to find equivalent resistance + the current through each resistance and through every part of the circuit if the same. There is only one path for current to flow in a series circuit, so all resistors must have the same current flowing through them. SAME CURRENT at EACH RESISTOR + the voltage lost in each resistance can be different, but the sum of the voltages will always equal the voltage of the battery - parallel circuit: provides multiple paths for electrons to get through the resistive part of the circuit; connect devices along branched pathways. In a simple parallel circuit, each branch is connected to the same two points where a battery is also connected. The battery supplies voltage, which, like a heart, 'pumps' current through the circuit. These multiple pathways allow the total current to divide among the branches, but it also means that the voltage across each branch is the same + each time a new path is added to a parallel circuit, the total resistance will decrease no matter how high the resistance is of the new path. 1/R(eq) = 1/R(1) + 1/R(2) + 1/R(3) --> then at the end the fraction is flipped to get R(eq) + if the total resistance decrease, then the total current leaving and returning to the battery will increase. + the current through each path can be different, but the SUM of all the currents will equal the TOTAL current. The current is being split in multiple ways, so RESISTORS in parallel DO NOT HAVE SAME CURRENT through them. ** Can find the total curren

Relate electric currents to magnetic fields and describe the application of these relationships, such as in electromagnets, electric current generators, motors, and transformers.

- electric current produces a magnetic field - faraday's law: a magnetic field produces an electric current, as long as the magnetic field is changing + the process of generating electric current with a changing magnetic field is called electromagnetic induction (when a voltage is induced by a changing magnetic field). It occurs whenever a magnetic field and an electric conductor, such as a coil of wire, move relative to one another. As long as the conductor is part of a closed circuit, current will flow through it whenever it crosses magnetic field lines. One way this can happen is pictured in Figure below. It shows a magnet moving inside a wire coil. Another way is for the coil to move instead of the magnet. + With electromagnetic induction, an electric current can be produced in a coil of wire by moving a magnet in or out of that coil, or by moving the coil through the magnetic field. Either way, voltage is created through motion. + The amount of voltage induced depends on the number of loops in the coil of wire, as well as the speed at which the magnet is moved through the coil. A greater number of coils means a greater amount of voltage is induced. Similarly, the faster the magnet is moved through the coil, the more voltage you get. The magnetic field in space around an electric current is proportional to the electric current which serves as its source, just as the electric field in space is proportional to the charge which serves as its source. Ampere's Law states that for any closed loop path, the sum of the length elements times the magnetic field in the direction of the length element is equal to the permeability times the electric current enclosed in the loop. - Ampere's law used to quantify magnetic field of an infinitely long straight wire: B = μI/(2πr) where B is the magnetic field (Tesla), I is cur

Differentiate between atoms and their isotopes, ions, molecules, elements, and compounds.

- matter: anything with mass and that takes up space - substance: a pure form of matter (i.e. water) - mixture: contains more than one type of substance (i.e. steel, air) - elements: a substance compose of ONE type of atom - molecule: a group of 2 or more atoms/elements chemically bonded together - compound: a group of two or more different atoms/elements chemically bonded together--> all compounds are molecules but not all molecules are compounds - ions: an atom that has gained or lost one or more electrons and therefore has a negative or positive charge + Cation: an atom that has lost a valence electron and therefore has more positive protons than negative electrons, so it is positively charged + anion: an atom that has gained valence electron(s) and is negatively charged + Predicting the charge of an ion: *remember octet rule --> they want 8 valence electrons to have a full valence shell - Group IA has one valence electron, so it loses it and becomes +1 charged. - Groups IIA and IIIA lose two and three electrons, respectively, to become charged +2 and +3. - Group IVA can go either way, either losing or gaining four electrons. It rarely forms ions, though. - Group VA, with its five valence electrons, is when things change. - Group VA will gain three electrons to become negatively charged: -3. - Group VIA becomes -2 charged ions. - Group VIIA has seven electrons in its outer shell, so it gains one electron to become -1 charged. - Group VIIIA is the lucky group. This is the noble gas group with full valence electron shells, and they are happy just the way they are - Polyatomic ions you will commonly come across include the sulfate ion (SO42-), the hydrogen carbonate (bicarbonate) ion (HCO3-), the carbonate ion (CO32-), the hydroxide ion (OH-), the nitrate ion (NO3-), and the ammonium ion (NH4+) - isotopes: atoms

Demonstrate knowledge of the physical and chemical characteristics, including pH, of acids, bases, and neutral solutions.

- pH scale: pH= -log [h+]; logarithmic scale (from one pH unit to the next, the concentration of H+ changes by 10x); used to represent the level of acidity in a solution + pH below 7 is an acid + pH above 7 is basic + pH of 7 is neutral; water can break down to form H+ and OH- ions, when these ions are equal to each other, the value is 1 x 10-7 - the pH scale is based on the concentration of H+ ions in a solution (H+ ions actually exist as H3O+ in solution) - pH actually means the hydrogen (H) potential (p) of the solution - water exists in an equilibrium with the hydronium ion (H3O+) and the hydroxide ion (OH-) - when acids are added, they release more hydrogen ions into the solution --> more hydrogen ions = a lower pH and more acidic solution ACIDS: - Weak acids: partially release the hydrogen atoms that are attached; may lower pH by dissociation of hydrogen ions but not completely; Ex: acetic acid (vinegar), citric acid (citrus fruits) - Strong acids: completely dissociate and release ALL of their hydrogen atoms--> more potent in lowering the pH of a solution; Ex: (there are 7 strong acids): hydrochloric acid (stomach acid) and sulfuric acid (corrosive acid in batteries and fertilizers) - Turns blue litmus paper RED - Taste SOUR in aqueous solutions - some acids are corrosive - Form SALTS through reactions with some metals and bases - The body require acids to maintain them: + Hydrochloric acid: produced in stomach to assist in digestion + Fatty acids: released when the body breaks down fats for energy + ATP acts like an acid because when added to a solution, ATP releases hydrogen ions + Nucleic acids: responsible for genetic makeup + Amino acids also release a small amount of hydrogen ions into aqueous solutions BASES: describe solutions greater than 7 - Potential for accepting rather than released hydrog

Apply knowledge of physical changes of matter and physical properties of matter.

- physical changes of matter: phase change: a transition of matter from one state to another + freezing: liquid to solid + melting: solid to liquid + sublimation: solid to gas + deposition: gas to solid + condensation: gas to liquid + vaporization: liquid to gas + ionization: gas to plasma + recombination: plasma to gas - endothermic: energy must be added to the system. I.e. turning a solid to liquid (melting) or liquid to gas (vaporization) - exothermic: energy is released from the system as the substance changes state. I.e. turning a gas to liquid (condensation) or liquid to solid (freezing) - Physical property: a characteristic that can be observed and measured without changing the composition of the same; can be used to describe mixtures and pure substances --> Pure substances have uniform and unchanging compositions, they also have consistent and unchanging physical properties + Extensive physical properties: those that are dependent on the amount of substance present * Volume: the amount of three-dimensional space occupied by a material + Intensive physical properties: those that do not depend on the amount of the substance present * Density: determined by dividing the mass of a given amount of a substance by its volume (g/mL); Will be the same no matter how much of it you have * Odor: used to identify chemicals and materials such as spices * Hardness: measurable and often recorded using the Moh's hardness scale * Color o Appearance, texture, color, odor, Melting point, Boiling point, density, solubility, polarity

Demonstrate knowledge of the central role of carbon in the chemistry of living systems.

- proteins, nucleic acids, carbohydrates, and lipids (all macromolecules) contain carbon; all living things contain carbon in some form - carbon is an integral part of many biological processes, including reproduction, photosynthesis, and respiration - carbon's molecular structure allows it to bond in many different ways with many different elements. + Individual carbon atoms have an incomplete outermost electron shell. With an atomic number of 6 (six electrons and six protons), the first two electrons fill the inner shell, leaving four in the second shell. Therefore, carbon atoms can form four covalent bonds with other atoms to satisfy the octet rule. + The methane molecule provides an example: it has the chemical formula CH4. Each of its four hydrogen atoms forms a single covalent bond with the carbon atom by sharing a pair of electrons. This results in a filled outermost shell. - carbon cycle shows how it moves through living and non-living aspects of the environment - hydrocarbons: molecules that contain only carbon and hydrogen and that can form chains and rings due to the bonding patterns of carbon atoms + hydrocarbons can have single, double, or triple bonds between carbon atoms (affects the geometry/3D shape of the molecules which affects the function) + the covalent bonds between the atoms in hydrocarbons store high amounts of energy, which can be released when these molecules are burned (oxidized) + hydrocarbon benzene rings (rings of hydrocarbons with double bonds) are present in many biological molecules including some amino acids and most steroids (lipids), which includes cholesterol and estrogen and testosterone hormones + in triglycerides (fats and oils), long carbon chains known as fatty acids may contain double bonds that can be in either cis (liquid at room temperature) or trans (solid at roo

Demonstrate knowledge of the energy changes that accompany changes in states of matter.

- the temperature of a substance increases as it is heated. Temperature is the average kinetic energy of the substance, where energy is the ability to do work. Heat is the total energy contained within a substance. As a solid is heated, its temperature increases as the molecules move faster. During the phase change, when solid melts into liquid, its temperature remains constant as the heat energy is stored as potential energy. Likewise, as heat is added to a liquid, its temperature increases as the molecules, once again, move faster. When the liquid reaches its boiling point and boils, the temperature remains constant as, once again, the added heat is stored as potential energy during the phase change. Finally, impurities will change the melting point and the boiling point of compounds. - Fusion, vaporization, and sublimation are endothermic processes, whereas freezing, condensation, and deposition are exothermic processes. - Changes of state are examples of phase changes, or phase transitions. - All phase changes are accompanied by changes in the energy of a system. Changes from a more-ordered state to a less-ordered state (such as a liquid to a gas) are endothermic. Changes from a less-ordered state to a more-ordered state (such as a liquid to a solid) are always exothermic. - The conversion of a solid to a liquid is called fusion (or melting). The energy required to melt 1 mol of a substance is its enthalpy of fusion (ΔHfus). - The energy change required to vaporize 1 mol of a substance is the enthalpy of vaporization (ΔHvap). - The direct conversion of a solid to a gas is sublimation. The amount of energy needed to sublime 1 mol of a substance is its enthalpy of sublimation (ΔHsub) and is the sum of the enthalpies of fusion and vaporization. - Plots of the temperature of a substance versus heat added or v

Predict charges or poles on the basis of attraction/repulsion observations.

- there are two types of magnetic poles: north magnetic pole and south magnetic pole. + north magnetic poles are those that are attracted toward the Earth's geographic north pole + like poles repel and unlike poles attract + magnetic poles always occur in pairs of north and south; it is not possible to isolate north and south poles + all magnetism is created by electric current + ferromagnetic materials, such as iron, are those that exhibit strong magnetic effects. the atoms in ferromagnetic materials act like small magnets (due to currents within the atoms) and can be aligned. These materials are strongly attracted to magnets. Here are some characteristics of a magnetic field: - The lines of flux travel through the magnet - They leave the magnet at the north pole. - They travel through the air in a curve. - The lines enter the magnet at the south pole. - A line tangent to any point on a line of flux shows the direction of the field - which is the direction of the force that would be exerted on a north pole. - Where the lines are close together the field is the strongest. - The direction of the field is NORTH to SOUTH. The arrows point away from the north pole and towards the south pole.

Compare and contrast the transmission, reflection, and absorption of light in matter.

- white light contains all of the wavelengths/colors of visible light + the color of an object depends on which wavelengths of light it absorbs and which is reflects. white objects reflect all of the light that hits them and absorbs none. black objects reflect none but absorbs all of the light that hits them. A red surface absorbs all of the wavelengths except for red, which is reflected. + the sky looks blue because the white light from the sun hits the molecules in our atmosphere and causes the shorter blue wavelengths to scatter out in all directions - When light shines on an object, it is reflected, absorbed, or transmitted through the object, depending on the object's material and the frequency (color) of the light ABSORPTION: When light is absorbed, the energy is taken in by the material. The energy within the material increases, causing the particles to move faster. This energy eventually radiates as heat. - Ex: heat rising from pavement after the sun has been shining on it for awhile - Absorption occurs when photons from incident light hit atoms and molecules and cause them to vibrate. The more an object's molecules move and vibrate, the hotter it becomes. This heat is then emitted from the object as thermal energy. - Some objects, such as darker colored objects, absorb more incident light energy than others. For example, black pavement absorbs most visible and UV energy and reflects very little, while a light-colored concrete sidewalk reflects more energy than it absorbs. Thus, the black pavement is hotter than the sidewalk on a hot summer day. Photons bounce around during this absorption process and lose bits of energy to numerous molecules along the way. This thermal energy then radiates in the form of longer wavelength infrared energy. REFLECTION: When light is reflected, the material fails to absorb th

Apply knowledge of electromagnetic radiation, including analyzing evidence that supports the wave and particle models that explain the properties of electromagnetic radiation.

EM radiation: defined as the movement of energy through space or a medium, comprising both an electric and magnetic wave that oscillate at right angles to each other and to the direction of wave travel. Each EM wave has both frequency and wavelength, the latter being defined as the distance between positive or negative wave peaks in either the electric or magnetic waves. Wavelength is easily calculated as the speed of light divided by the frequency, like in this equation provided here: 𝜆 = c/f where 𝜆 is the wavelength in meters, c is the speed of light 3 x 10^8 m/s, f is the frequency in hertz (1/s) - example: a particular wave if electromagnetic radiation has a frequency of 1.5 x 10^14 Hz. What is the wavelength of the wave? 𝜆 = c/f so 𝜆 = (3 x 10^8 m/s)/(1.5 x 10^14 Hz) = 2.00 x 10^-6 m All electromagnetic radiation travels through a vacuum at the same speed, called the speed of light. Its speed in any given medium depends on its wavelength and the properties of that medium. Electromagnetic waves can be classified and arranged according to their various wavelengths/frequencies; this classification is known as the electromagnetic spectrum - Highest frequency/lowest wavelength to lowest frequency/highest wavelength: gamma rays, x-rays, UV, visible light (shortest wavelength to highest wavelength: blue, green, yellow, red), infrared radiation, microwave, radio waves - To the right of the visible spectrum, we find the types of energy that are lower in frequency (and thus longer in wavelength) than visible light. These types of energy include infrared (IR) rays (heat waves given off by thermal bodies), microwaves, and radio waves. These types of radiation surround us constantly, and are not harmful, because their frequencies are so low. lower frequency waves are lower in energy, and thus are not dangerous

Demonstrate knowledge of how energy is stored and can change in electric and magnetic fields.

Electricity and magnetism are inextricably linked. Under certain conditions, electric current causes a magnetic field. Under other conditions, a magnetic field can cause an electric current. A moving charged particle creates a magnetic field around it. Additionally, when a moving charged particle moves through a different magnetic field, the two magnetic fields will interact. The result is a force exerted on the moving charged particle. - The energy of a capacitor is stored in the electric field between its plates. Similarly, an inductor has the capability to store energy, but in its magnetic field. - Electric forces and magnetic forces are different aspects of a single electromagnetic interaction. Such forces can be attractive or repulsive, depending on the relative sign of the electric charges involved, the direction of current flow, and the orientation of magnets. The forces' magnitudes depend on the magnitudes of the charges, currents, and magnetic strengths as well as on the distances between the interacting objects. All objects with electrical charge or magnetization are sources of electric or magnetic fields and can be affected by the electric or magnetic fields of other such objects. Attraction and repulsion of electric charges at the atomic scale explain the structure, properties, and transformations of matter and the contact forces between material objects. Coulomb's law provides the mathematical model to describe and predict the effects of electrostatic forces (relating to stationary electric charges or fields) between distant objects. Coulomb's law gives the magnitude of force between point charges: F = k x | q1*q2 |/r^2 where q1 and q2 are two point charges separated by distance r and k is 8.99 x 10^9 N*m^2/C^2 - Electric and magnetic fields also contain energy; any change in the relative positions of char

Demonstrate knowledge of the relationship between wave frequency, wavelength, and amplitude and energy.

Frequency (f): number of waves passing a specific point per second F = 1/T - Unit: Hz or (s^-1) --> one cycle (one wave) per second Wavelength (𝜆 ): the distance between adjacent identical parts of a wave, parallel to the direction of propagation --> unit: meters or nm + The distance between two wave crests or two wave troughs, expressed in various metric measures of distance + EM wave: 𝜆 = c/f, where 𝜆 is the wavelength in meters, c is the speed of light 2 x 10^8 m/s, and f is frequency in hertz or 1/s Amplitude: distance between the resting position (null point) and the maximum displacement of the wave Energy: related to its amplitude and frequency --> in Joules - EM wave: + Energy of an EM photon: E = hv where h is Planck's constant and v is the frequency of the light absorbed or emitted + Photon: the elementary particle, or quantum, of light that can be absorbed or emitted by atoms and molecules + Shorter wavelength = higher frequency = higher energy - Mechanical wave: + In a mechanical wave, the energy, frequency, and amplitude are related. + The greater the energy in the wave, the greater the movement of the particles from their resting position and so the greater the amplitude. + The higher the frequency, the faster the particles oscillate and so the greater the amount of energy in the particles + Wave amplitude of a longitudinal wave is the distance between particles of the medium where it is compressed by the wave. Wave amplitude is determined by the energy of the disturbance that causes the wave. A wave caused by a disturbance with more energy has greater amplitude. amplitude: how far the molecules of the medium have moved from their normal rest position Period: the time it takes for one wave cycle to complete, number of seconds per wave T =1/ f --> unit: seconds Wave velocity

Identify fundamental forces, including gravity, nuclear forces, and electromagnetic forces (magnetic and electric), and recognize their roles in nature, such as the role of gravity in maintaining the structure of the universe.

GRAVITY: attraction between 2 objects that have mass - Causes ocean tides - Gravity holds planets, stars, solar systems, and galaxies together - infinite range - weakest WEAK NUCLEAR FORCE: responsible for particle decay (change of one type of subatomic particle into another) and thus radioactivity - Critical for nuclear fusion reactions that power the sun and produce the energy needed for most life forms - Allows us to date fossils/rocks - Beta decay (neutron into proton and ejects an electron or a proton turns into a neutron and ejects a positron) --> only the action of the weak force changing protons into neutrons within a star like the sun allows nuclear fusion to get off the ground within its core at all. The burning of stars - and so the existence of life - depends on the weak force. - short range: within the diameter of a nucleus - 2nd weakest ELECTROMAGNETIC: acts between charged particles - Opposite charges attract one another, wile like charges repel - The greater the charge, the greater the force - Consists of the electric and magnetic force - Responsible for some of the most commonly experienced phenomena: friction, elasticity, the normal force, the force holding solids together in a given shape - Responsible for drag on flying objects - These actions can occur because of charged particles interacting with one another - atoms: electrons are kept in the orbit around the nucleus by the electromagnetic force, because the nucleus in the center of the atom is positively charged and attracts the negatively charged electrons. - light - chemical bonding - infinite range - 2nd strongest STRONG NUCLEAR FORCE: binds the fundamental particles of matter together to form larger particles. It holds together the quarks that make up protons and neutrons, and part of the strong force also keeps the protons and neutrons o

Evaluate evidence that indicates that certain wavelengths of electromagnetic radiation may affect living cells.

Ionizing and non-ionizing radiation: - an important aspect of EM radiation is ability to ionize atoms. recall that an ion is an atom that has lost or gained electrons, and so carries a positive or negative charge - the ability of EM radiation to ionize an atom is part of the photoelectric effect and is related to the frequency of light. the higher the frequency, the more likely it is that the EM radiation will ionize an atom - high frequency EM radiation includes UV light, x-rays, and gamma rays. these are able to knock electrons from atoms. if this occurs in body tissue, free radicals (groups of highly reactive atoms) may be produced causing tissue damage. Free radicals are atoms that contain an unpaired electron. Due to this lack of a stable number of outer shell electrons, they are in a constant search to bind with another electron to stabilize themselves—a process that can cause damage to DNA and other parts of human cells - EM radiation with longer wavelengths and therefore lower frequencies are unable to ionize atoms. these wavelengths are therefore called non-ionizing radiation biological damage: - recall that radioactive material decays by alpha, beta, or gamma radiation. when alpha or beta decay occurs, alpha and beta particles are ejected from the nucleus. these may cause tissue damage, especially if alpha and beta emitters are ingested. after particle ejection, the remaining nucleus may be in a high energy state. it reduces this energy by emitting gamma radiation - gamma radiation has much higher penetrating power than alpha or beta emissions. as a result, it can pass right through the body. as it travels through the body, the gamma ray may hit molecules of DNA, knocking electrons loose and producing ionization events. these damage the DNA by affecting the bonds between atoms or producing highly reactive

Demonstrate knowledge of resonance and of the reflection, refraction, and transmission of waves.

It essenetially depends on the material they hit **look at document for illustrations RESONANCE: when one object vibrating at the same natural frequency of a second object forces that second object into vibrational motion - The increase in the amplitude of an oscillation of a system under the influence of a periodic force whose frequency is close to that of the system's natural frequency - Resonance is a phenomenon in which waves add up in phase (i.e., matched peaks and valleys), thus growing in amplitude. Structures have particular frequencies at which they resonate when some time-varying force acting on them transfers energy to them. This phenomenon (e.g., waves in a stretched string, vibrating air in a pipe) is used in the design of all musical instruments and in the production of sound by the human voice. REFLECTION: the change in direction of a wave when it bounces off a barrier (such as a fixed end) - When the wave hits the fixed end, it changes direction, returning to its source. As it is reflected, the wave experiences an inversion, which means that it flips vertically. If a wave hits the fixed end with a crest, it will return as a trough, and vice versa - Regardless of the angle at which the wavefronts approach the barrier, one general law of reflection holds true: the waves will always reflect in such a way that the angle at which they approach the barrier equals the angle at which they reflect off the barrier. This is known as the law of reflection - angel of incidence (I) and angle of reflection (R) - A ray of light is incident towards a plane mirror at an angle of 30-degrees with the mirror surface. What will be the angle of reflection? + The angle of reflection is 60 degrees. (Note that the angle of incidence is not 30 degrees; it is 60 degrees since the angle of incidence is measured between the incide

Identify the separate forces that act on a system (e.g., gravity, tension/compression, normal force, friction), describe the net force on the system, and describe the effect on the stability of the system.

Non-contact forces: - Gravity: a property of all masses that causes them to pull together + Acceleration of gravity (g): 9.8 m/s2 + Weight (measured in N) = mg + Free fall: a special type of motion in which gravity is the only force acting on an object + During free fall problems, we substitute g for a in acceleration equations; g= -9.8 m/s2 and the negative sign indicates the acceleration is in the downwards direction. During free fall, a point is reached at which gravitational force is equal to the opposing force of air resistance. At this point, the object stop accelerating and falls at a constant velocity. This is called terminal velocity. Surface area is very important when determining terminal velocity. The greater the surface area, the greater the air resistance, and the slower the terminal velocity + Air resistance/drag: the force opposing the downward acceleration due to gravity. It is due to contact with air particles as the object pushes through them. - Electric force: the attraction or repulsion between two charged objects - Magnetic force: force exerted between two magnetic poles; can be push or pull Contact forces: - Normal force: always perpendicular to the surface: when an object comes in contact with a surface, that surface exerts a force on the object which resists changes in the surface; a force that balances the weight on an object on a surface + It's a force of resistance: prevents the surface from deforming or breaking due to force applied through contact with an object + Always in the opposite direction of the force applied. + If the force is a pull, the direction of the normal force is away from the surface + When an object is placed on the ground, the ground exerts a normal force on the object equal to the force of gravity acting on the object (its weight) + It is exerted whenever an

Demonstrate knowledge of the definitions of power, voltage differences, current, and resistance and calculate their values in simple circuits.

Ohm's Law: V= I x R + the current is directly proportional to the voltage and inversely proportional to the resistance + increasing the voltage and inversely proportional to the resistance + increasing the voltage will cause the current to increase, while increasing the resistance will cause the current to decrease - Power: the rate at which a circuit uses electrical energy; measured in Watts: P= V * I or P = V^2/R - Resistance: a measure of how much an object impeded an electric current (the flow of electrons); measured in Ohms and affected by: + the resistivity of the material (related to the number of free electrons present) + the dimensions of an object (wire) because increasing the length of electrons have to travel will increase the resistance while increasing the cross-sectional area through which the electrons will flow will decrease the resistance + the temperature: as the temperature of the conductor increases, so will its resistance - Voltage differences: + voltage: the electrical potential energy per unit charge; electric pressure created by a power source, such as a battery + voltage drop: the loss of electrical power as a current travels through a resistor, wire or other componenet - Current: The flow of charge through an electric circuit past a given point of measurement + current flows from the negative terminal of our power supply, through the circuit, and back to the positive terminal of the power supply as it completes the loop. As current passes through resistors along the circuit there's a voltage drop (loss in voltage). The total loss of voltage around a circuit loop will equal the total voltage of the power supply. So, if you have a 12V battery powering the circuit and you have three resistors along that circuit, you'll have a total loss of 12V across the resistors. In contrast, as c

Demonstrate knowledge of the ways in which energy manifests itself at the macroscopic level (e.g., motion, sound, light, thermal energy).

mechanical energy: energy due to an object's motion or position - Mechanical motion is the physical motion of objects. This is probably the most apparent or intuitive manifestation of energy. We see it when we move our arm, when the tires of a car or bicycle spin, or when a ball falls from a cliff. When a mom tells a kid they need to go 'burn off some energy,' typically she means to go run around for a while. We think of movement as a result of energy. - Mechanical motion is often what we want to ultimately accomplish with energy. We want to move our arms, so we transfer electrons from food to our body. Heat energy may be generated in this process, but it's all to move our arms and pump our heart. - Sound energy is a form of mechanical energy that starts with a vibration in matter. For example, the singer's voice starts with vibrations of his vocal cords, which are folds of tissue in his throat. The vibrations pass to surrounding particles of matter and then from one particle to another in waves. Sound waves can travel through air, water, and other substances, but not through empty space. + The manifestation of sound energy is similar to light energy, as both move as waves. Our ears interpret waves of compressed air as sound. These sound waves occur when something vibrates (for example, a guitar string) or merely when air is compressed in some way (for example, dropping a box on the ground), which creates pressure waves. A good illustration of this is how our vocal chords vibrate to create sounds when we speak. + We could think of sound energy as motion, but the motions are on such a small scale that we can't see it occurring. But our ears are able to pick up on this motion and translate it into sound. chemical energy: stored energy released through chemical reactions - Fuels, such as gasoline and food, carry chemic