Conceptual physics final (summer)
induced
when charge is redistributed on an object because of the presence of a charged object nearby.
Electrically polarized
when the charges in an atom or molecule are aligned to that one side is slightly more positive or negative than the opposite side.
How do atoms emit light?
1. collision with a moving particle (excites atom) 2. Jumps to higher energy level 3. drops back down through the release of a light photon
Describe the conditions for a bow wave to occur.
A bow wave occurs when something moves faster than eave speed on water.
Circut
A closed path through which an electric current flows or may flow.
Voltage source
A device, such as a generator or a battery, that provides a potential diffrences
Rarefaction
A disturbance in air (or matter) in which the pressure is lowered. Opposite of compression.
Wave
A disturbance that repeats regularly in space and time and is transmitted progressively from one place to the next with no actual transport of matter
mirage
A floating image that appears in the distance and is due to the refraction of light in Earth's atmosphere.
Alternating Current (AC)
A flow of electric charge that regularly reverses its direction.
natural frequency
A frequency at which an elastic object, once energized, will vibrate. Minimum energy is required to continue vibration at that frequency. Also called resonant frequency.
Distinguish between a good conductor and a good insulator
A good conductor has free electrons and can efficiently conduct electricity Ie iron, water, copper A good insulator is a poor conductor of electricity ie Wood, plastic, rubber
Distinguish between a group and a period
A group is a vertical column on the periodic table and a period is a horizontal row.
Period
A horizontal row of elements in the periodic table
Normal
A line perpendicular to a surface
Compound
A material in which atoms of different elements are chemically bonded to one another
Semi-conductor
A material that can act both as a conductor and as an insulator
Describe the present model of an atom
A nucleus containing the protons and the neutrons. This is surrounded by electrons that orbit in shells. The first shell can only hold two electrons but subsequent ones can hold eight.
interference pattern
A pattern formed by the overlapping of two or more waves that arrive in a region at the same time.
beats
A periodic variation in the loudness of sound caused by interference when two tones of slightly different frequencies are sounded together.
convex lens
A piece of transparent glass curved so that the middle is thicker than the edges, converges light like >
Element
A pure substance made of only one kind of atom
vibration
A repeated back and forth motion about and equilibrium position.
Explain the characteristics of a series circuit
A series circuit has multiple resistors in a row. Each resistor increases total resistance.
Describe the conditions for a sonic boom to be heard.
A sonic boom can only be heard when an object (usually a jet) goes faster than the speed of sound and passes you. You cannot hear the boom until the object passes you.
opaque
A term used to describe a material that absorb light without re emission and consequently do not let light through.
Give examples of forced vibration
A tuning fork held against a table will vibrate a table (but for a shorter time because vibrating a table takes a lot more energy than vibrating the fork.) (Conservation of energy) The vibrations from a piano vibrate the lid and amplify the sound because it is a larger surface to interact with and vibrate the air. guitar violin
Longitudinal wave
A wave in which the vibration of the medium is parallel to the direction the wave travels
EM wave
A wave that is partly electric, partly magnetic, that carries energy and is caused by vibrating electric charges.
Transverse wave
A wave with vibrations at right angles to the direction of wave travel
Chemical symbol
Abbreviated way to write the name of an element
Constructive interference
Addition of two or more waves when crests overlap and produce a wave with increased amplitude.
Grounding
Allowing charges to move freely along a connection between a conductor and the ground.
Describe the drift speed of conduction electrons in a current carrying wire
Although electrons inside metal at room temperature have an average speed of a few million kilometers per hour, they make no current because they are moving in all possible directions. There is no net flow in any preferred direction. But, when a battery or generator is connected, an electric field is established inside the conductor. The electrons continue their random motions while simultaneously being nudged by this field. It is the electric field that can travel through a circuit at nearly the speed of light. The conducting wire acts as a guide or "pipe" for electric field lines.
doppler effect
An apparent change in the frequency of waves, as of sound or light, occurring when the source and observer are in motion relative to each other, with the frequency increasing when the source and observer approach each other and decreasing when they move apart.
Isotope
An atom with the same number of protons (same atomic number) and a different number of neutrons from other atoms of the same element. (Different mass number)
Ion
An electrically charged atom with an excess or deficiency of electrons
Virtual image
An image formed through reflection or refraction that can be seen by an observer but cannot be projected on a screen because light from the object does not actually come to a focus.
Spectroscope
An instrument that separates light from a light source into its characteristic frequencies.
Nodes
Any part of a standing wave that remains stationary
Concave lens
Are lenses that are thinner in the middle than at the edge, diverges light like <
Identify and describe isotopes of common elements.
Atoms of the same element but have different amounts of neutrons are called isotopes, be careful not to confuse these with ions. isotopes are denoted by their mass number (protons+neutrons) (ions are atoms that have been electrically charged due to a deficiency or surplus of electrons.)
explain the configuration of a working circuit
Battery or other voltage source | | switch | | | light bulb or other resistor'___|
Equations Beats ohms law power relationship between frequency and period speed of light resistors in series and resistors in parallel velocity wave velocity coulombs law
Beats: ft= f1 - f2 ohms law: I = v/r or V= IR power: P= IV relationship between frequency and period: inverse so f= 1/T and T= 1/f speed of light: 3* 10^8 resistors in series and resistors in parallel: Parallel: 1/R= 1/R + 1/R + 1/R....... Series : R= R + R + R+.... velocity: V= d/t (unit: m/s) wave velocity: V= Wavelength * frequency coulombs law: F= (9*10^9) * q1 * q2 / d^2
What causes the dispersion of light?
Because light of different frequencies travels at different speeds in transparent materials, it refracts by different amounts. When white light is refracted twice, as in a prism, the separation of the different colors of light is quite noticeable. This separation of light into colors arranged according to frequency is called dispersion The light rays sort of spread out
Why is glass transparent to visible light but opaque to ultraviolet and infrared?
Because the natural vibration frequency for electrons in glass is the same as the frequency of ultraviolet light, resonance occurs when ultraviolet waves shine on glass. The absorbed energy is passed on to other atoms as heat, not reemitted as light, making the glass opaque at ultraviolet frequencies. In the range of visible light, the forced vibrations of electrons in the glass are at smaller amplitudes—vibrations are more subtle, reemission of light (rather than the generation of heat) occurs, and the glass is transparent. Lower-frequency infrared light causes whole molecules, rather than electrons, to resonate; again, heat is generated, and the glass is opaque to infrared light.
Explain how current can be turned on or off in a circuit, and explain how electrical devices can be connected in a circuit
By using a switch or connecting or disconnecting or connecting the voltage source Either in series or in parallel
Why are clouds white?
Clouds are white because their water droplets or ice crystals are large enough to scatter the light of the seven wavelengths (red, orange, yellow, green, blue, indigo, and violet), which combine to produce white light.
destructive interference
Combination of waves where crests of one wave overlap troughs of another, resulting in a wave of decreased amplitude.
Distinguish between ac and dc
DC the current flows in one direction. In AC the current oscillates changing direction by alternating the polarity of the voltage. AC is what flows through the powerlines and in the united states runs at 60 HZ
Ultrasonic
Describes a sound of a frequency too high to be heard by the normal human ear---above 20,000 hertz
What determines whether a material reflects, transmits, or absorbs a certain type of light?
Different materials have different natural frequencies for absorbing and emitting electromagnetic radiation. In one material, electrons oscillate readily at certain frequencies; in another material, they oscillate readily at different frequencies. At the resonant frequencies at which the amplitudes of oscillation are large, light is absorbed, and the energy is turned into heat. Glass is opaque to uv radiation and uv waves will just heat up glass because its frequency matches the resonant frequency of glass. but at frequencies below and above the resonant frequencies, light is reemitted. If the material is transparent, the reemitted light passes through it. (transmitted) If the material is opaque, the reemitted light returns to the medium from which it came. This is reflection.
Direct Current (DC)
Electric current that flows in only one direction
Excited state of an atom
Electron or electrons have moved to a higher energy level
What is happening inside a current carrying wire
Electrons are flowing
Describe, from the point of electron transfer, how an object becomes positively or negatively charged.
Electrons can rub off onto or off an object. Thus giving it a charge
Write out and explain coulomb's law.
F= (9*10^9) * q1 * q2 / d^2 force = k * charge one * charge two divided by distance squared This equation helps us find the force between two charges
As long as a planet has liquid water and any amount of oxygen in its atmosphere, it can support life, regardless of what other gases besides oxygen are in the atmosphere.
False
Edwin Hubble used the most powerful telescope of his day and was thus able to confirm the common belief that our Milky Way galaxy is the only galaxy in the universe.
False
Famous astronomer, Carl Sagan agreed with the Bible that "the heavens declare the glory of God," and "the earth is the LORD's, and all who dwell in it."
False
Guillermo Gonzalez is an astrobiologist research scientist who started out trying to prove that the earth is unique in its ability to support life.
False
It doesn't matter very much what the mix of gases are on a planet because living organisms are so adaptable that life would just evolve differently
False
SETI (the Search for Extraterrestrial Intelligence) is research based on the belief that the earth is a completely unique planet in the universe because unlike other planets, it can support life.
False
The Galactic Habitable zone is an area in a galaxy very close to the center where the high number of exploding stars and strong radiation would help complex life thrive.
False
The founders of modern science (Copernicus, Galileo, Kepler, and Newton) were atheists who believed that learning the laws of science made knowledge of God unnecessary.
False
The heliocentric model of the universe (the earth moves in orbit around the sun) came from the Greek philosophers Ptolemy and Aristotle, which people believed for 18 centuries until the time of Copernicus.
False
The laws of physics that govern the structure of the universe are horribly complicated and their mathematical formulas are almost impossible to understand
False
The moon is nice to look at but does nothing to help the earth support complex life
False
The possibility is high that of all the factors needed to sustain complex life on a planet would occur at the same time.
False
In parallel
For instance when resistors or light bulbs are connected at two or more points so that current has alternate paths to flow
In series
For instance when resistors or light bulbs are connected in a row so that the current that goes through one must go through all of them
Describe the relation between frequency and period to a wave
Frequency and period are inversely related. (one goes up when one goes down)
White light
Light like sunlight that is a combination of all the Roy G biv colors
scattering
Light or sound is absorbed and re emitted in all directions
Distinguish between line and continuous spectra
Line spectra is black strip with colored lines representing the reflected wavelengths of light whereas a continuous spectra is a rainbow line with black absorption lines.
Trough
Lowest point of a wave, disturbance is the greatest in the opposite direction than the crest
Calculate atomic mass and mass number of an atom.
Mass number is the number of protons plus the number of neutrons in an atom. (The rounded number we have been using) No label and is how we identify isotopes. Atomic mass is the number that appears for mass on the periodic table that has the decimal and is the exact mass of an atom based on isotopes. We're really focused on mass number. Don't confuse mass number with atomic mass. Mass number is an integer that specifies an isotope and has no units—it's simply the number of nucleons in a nucleus. Atomic mass is an average of the masses of isotopes of a given element, expressed in atomic mass units (amu).
calculate an isotopes proton, neutrons, electrons, mass number, atomic number, and charge when given its full symbol.
Mass number will always be bigger than atomic number because mass number is protons plus neutrons and atomic number is just protons. To find neutrons subtract the number of protons (atomic number) from the mass number. Protons = atomic number electrons will equal the number of protons unless the atom is charged. in which case the charge will say something like 2-. In this case there are two more electrons than protons because electrons are negative.
Insulator
Material that is a poor conductor
Conductor
Material through which electric charge can flow, usually metals
Explain the characteristics of a parallel circuit
Multiple paths for electricity to flow so each resistor decreases total resistance
Describe the parts of a standing wave and how they occur.
Nodes- Where the wave remains stationary Antinodes- Positions where the largest amplitudes occur The stationary wave pattern formed in a medium when two sets of identical waves pass through the medium in opposite directions. The wave appears not to be traveling. The result of wave interference.
Atomic number
Number of protons found in the nucleous
Reminder for pierce- add privileged planet terms
Obama
Resonance
Occurs when the frequency of forced vibrations on an object matches the object's natural frequency, and a dramatic increase in amplitude results.
What causes interference patterns and distinguish between constructive and destructive interference.
Occurs when two or more overlapping waves exist in the same space at the same time. In constructive interference the two-wave are in phase. This means that their amplitude is added together while they overlap. (magnify) In destructive interference, the crest of one overlapping wave lines up with the other waves through, the waves subtract amplitudes (cancel each other)
Describe Ohm's Law? Formula?
Ohm's Law= current, voltage difference and resistance in a circuit are all related. The current in a circuit equals the voltage difference divided by resistance. I=V/R
crest
One of the places in a wave where the disturbance is the greatest or the wave is the highest.
Why is water cyan?
Partially because of reflection from the sky also, because the Na molecules in the water absorb red light and thus reflect blue and green (water absorbs red light)
Describe the period of a pendulum and its dependance on length, mass, and gravity.
Period is the time it takes for a pendulum to makes a complete back and forth swing. The longer the pendulum is the longer it takes to make a complete swing. Gravity is what accelerates the pendulum. T(period) = 2(pi) * √L/G
describe the conditions for beats
Periodic vibrations in sound LOUDNESS. Beats are heard when two tones of slightly different frequencies interfere.
Describe what happens when an insulator is in the presence of a charged object.
Polarization occurs and one side of the object (the insulator) becomes more positive and one more negative. There is a net attraction, so they cling to each other
Relate power (Watts) to current (amps) and voltage (volts)
Power = Current * Voltage
Draw an isotopes protons, neutrons, and electrons when given its full symbol
Protons and neutrons in the middle protons are + Neutrons are neutral so N electrons go in rings around the nucleus (the first ring can hold two, but subsequent ones can hold eight) Atomic number is the number of protons and is on the top in the periodic table but on the bottom when you draw the symbol, in a neutral atom the number protons will match the number of electrons. The charge will tell you have more electrons (-) or more protons (+). Mass number is the number of protons plus the number of neutrons.
Three colors than can make almost any color
Red, Green, Blue
Additive primary colors
Red, blue, and green light. These colors when added together produce white light.
Ampere
SI unit of current. 1 amp = one coulomb per second
Coulomb
SI unit of electric charge
Relate a drawing of a sine curve to the crest, amplitude, troughs, and length of a wave
See picture
Compare the transmission of sound through air with solids, liquids, and vacuum
Sound travels the fastest through solids and the slowest through air. it moves faster in liquids than it does in air but not as fast as solids. Sound cannot travel in a vacuum because there is no medium.
Conditions necessary for seeing a rainbow!?
Sun in one part of the sky (behind you lower in the horizon), rain in the other (in front of you). All rainbows would be completely round if not for the ground. Drops of water act like prisms. Rainbow is caused by: as white light enters one rain drop, it refracts and disperses into Roy g biv, then Roy g biv has total internal reflection on the opposite side, then as it comes back and as it exits the raindrop it refracts again and further disperses. From one raindrop you only see one color, you see each color from a different drop The color of each drop of a rainbow is based on your position. Rainbow is a 3d cone with an apex at your eye In order to get the colors to disperse they must separate out into diff speeds. If the speed of light was the same in the raindrop they wouldn't separate, and rainbow would not work Everybody sees his or her own personal rainbow. Another fact about rainbows: A rainbow always faces you squarely because of the lack of distance cues mentioned earlier. When you move, your rainbow moves with you. So you can never approach the side of a rainbow, or see it nearly end-on as in the exaggerated view of Figure 28.33. You can't get to its end. Therefore the expression "looking for the pot of gold at the end of the rainbow" means pursuing something you can never reach.
equation for period
T=1/frequency (f)
Periodic table
Table of elements arranged according to repeated changes in properties.
transparent
Term applied to materials that allow light to pass through them in straight lines.
Infrasonic
Term applied to sound pitch too low to be heard by the human ear, that is, below 20 hertz.
In phase
Term applied to two or more waves whose crests (and troughs) arrive at a place at the same time, so that their effects reinforce each other.
Out of phase
Term applied to two waves for which the crest of one wave arrives at a point at the same time that a trough of the second wave arrives. Their effects cancel each other.
Pitch
Term that refers to how high or low sound frequencies appear to be
bow wave
The V-shaped wave produced by an object moving on a liquid surface faster than the wave speed.
Why is the sky blue?
The air molecules scatter blue light better than red light, so more blue light reaches our eyes.
Describe what happens to air when sound moves through it
The air molecules vibrate, thus vibrating the ones next to them, this process repeats a bunch until it runs out of energy because each vibration takes some energy.
Polarization
The aligning of vibrations in a transverse wave, usually by filtering out waves of other directions
Angle of reflection
The angle between the reflected ray and the normal to the surface
Reflection
The bouncing back of a wave or particle when it hits the boundary between two media
Describe the doppler effect and how it relates to red/blue shift in light.
The change in the frequency of a wave of sound or light due to the motion of the source or the receiver. The motion of distant galaxies makes them appear either red or blue. Blue if they are approaching because the frequency of blue light is higher and red if they are receding because the frequency of red light is lower. this is also true for sound, a fire truck driving towards you will have a higher pitched siren than one driving away because of the doppler effect.
Induction
The charging of an object without direct contact
How does the reflection of light affects somethings color and how black and white are not true colors
The color of light something reflects is the color it appears to our eyes White is the combination of all colors black is the absence of color
subtractive primary colors
The colors of magenta, yellow, and cyan. These are the three colors most useful in color mixing by subtraction.
Explain the causes of electric shock
The damaging effects are from the current (amps) running through the body The resistance the body provides to the current is what turns the electricity into heat or other things.
Describe factors that affect the speed of sound
The density of the medium, this makes it more efficient for molecules to vibrate each other. Interestingly, the denser an object is the slower sound travels through it. This is true even though sound travels the fastest in solids, the densest of the three states of matter. Explanation from Q & A: density and speed of sound | Department of Physics | University of Illinois at Urbana-Champaign It's true that the other things being equal, the speed of sound goes down as the mass density goes up. The problem is that other things usually aren't equal. A little ripple in the density of a piece of steel creates much bigger forces than a similar percentage ripple in the density of some air. So those bigger forces speed up the sound. Another way of saying that is that the sound speed goes up for bigger bulk modulus.
Amplitude
The distance from the midpoint to the crest. or equivalently, from the midpoint to the minimum (trough)
Electric current
The flow of electric charge measured in amperes
Relate the pitch of a sound to frequency
The higher the pitch the higher the frequency the lower the pitch the lower the frequency
explain why the image found in a plane mirror is a virtual image
The image is a virtual image because it cannot be viewed on a screen. The light rays are not actually emanating from the image and they never come to a focus.
Given the direction of the light striking a reflective surface, predict the path of reflection
The law of reflection states that the incident angle of light is the same as the angle at which the light is reflected
Critical angle
The minimum angle of incidence for which a light ray is totally reflected within a medium.
Mass number
The number of protons (atomic number) plus the number of neutrons.
What causes the refraction of light and what are its effects?
The refraction of light is when light enters a new medium where the speed of light is lowered. Examples of its effects are how fish in a pond seem closer to the surface than they actualy are and how straws don't line up with the submerged half when in glasses of water
Electric resistance
The resistance of a material to the flow of electric current through it; measured in ohms.
Sonic boom
The sharp crack heard when the shock wave that sweeps behind a supersonic aircraft reaches the listener
OHM
The si unit for electrical resistance
Hertz
The si unit of frequency. one HZ is one cycle per second.
Atom
The smallest particle of an element that has all of its chemical properties
Describe the fundamental rule at the base of all electrical phenomena
The terms positive and negative refer to electric charge, the fundamental quantity that underlies all electrical phenomena. The positively charged particles in ordinary matter are protons, and the negatively charged particles are electrons.
Forced vibration
The vibration of an object that is made to vibrate by another vibrating object nearby
Identify the source of conduction electrons in a circuit
The wire or circuit itself. the power source does not provide electrons.
Describe the conditions for the flow of electric charge
There must be a potential difference (voltage)
How are electrons arranged in an atom?
They orbit the nucleus in shells
Explain what the lines in a line spectrum represent and how such a spectrum can be used to identify the presence of an element.
They represent the wavelengths of light that are reflected, different elements reflect different combinations of wavelenths.
Cause and prevention of overloading household circuts
Too many devices on one line
After considering how solar eclipses allowed astronomers to learn about stars, scientists Guillermo Gonzales and Jay Richards proposed that "the same narrow circumstances that allow us to exist also provide us with the best overall setting for making scientific discoveries."
True
Albert Einstein believed itis easy to explain why it is that the universe happens to be understandable to us.
True
Astrobiology is a new area of science that studies what conditions are necessary for planets to support life.
True
If planets are too close or too far from a star then liquid water cannot exist and life cannot exists, which means a star like our sun has a "habitable zone."
True
If the sun were less massive, like 90% of the stars in the galaxy, its habitable zone would it would be closer where the stronger gravity would prevent the earth from rotating on its axis resulting in one side being burning hot and the other freezing cold.
True
Solar eclipses on earth allow astronomers to observe the sun's atmosphere and lean important things about stars; which would be impossible if the moon were not a nearly perfect match to the relative size of the sun.
True
The Copernican Principle, also known as the Principle of Mediocrity, means that the earth has no special place in the universe so we should not imagine that the universe was designed with us in mind.
True
The Laws of physics and chemistry determine that water is absolutely necessary for life and therefore life can only form on planets with liquid water.
True
The Voyager was a spaceship that took pictures in outer space, and its photograph of earth as "pale blue dot" prompted people to start to think about the significance of the earth in the universe.
True
The core of liquid molten iron at the center of the earth creates a magnetic field that keeps the earth's atmosphere from getting blown away by electromagnetic energy from the sun.
True
The position our planet occupies between two "arms" of the galaxy not only allows life to exist but also allows observers on earth to see other parts of the galaxy and learn about it.
True
if the gravitational force in the universe or strong nuclear force in Atoms were even a little bit different, it would be impossible for the universe to support life
True
Molecule
Two or more atoms that bond together by sharing electrons
Group
Vertical column in the periodic table
Standing wave
Wave in which parts of the wave remain stationary and the wave appears not to be traveling. The result of interference between an incident (original) wave and a reflected wave
Describe how to calculate the speed of a wave and what factors affect wave speed.
Wave speed equation: v=λ*f Wave speed depends on the medium wavelength and frequency vary inversely but will always produce the same wave speed.
How can an understanding of waves encourage our faith?
Waves obey the law of conservation of energy and thus cannot be instantly stopped at will. However, Jesus did this in matt 8:23-27 Then he got into the boat and his disciples followed him. 24Suddenly a furious storm came up on the lake, so that the waves swept over the boat. But Jesus was sleeping. 25The disciples went and woke him, saying, "LORD, save us! We're going to drown!" 26He replied, "You of little faith, why are you so afraid?" Then he got up and rebuked the winds and the waves, and it was completely calm. 27The men were amazed and asked, "What kind of man is this? Even the winds and the waves obey him!"
What happens when light reaches the boundary between two media
When a light wave strikes a boundary between two distinct media, a portion of the energy will be transmitted into the new medium and a portion of the energy will be reflected off the boundary and stay within the original medium.
Describe the conditions for diffuse reflection
When light is incident on a rough or granular surface, it is reflected in many directions. This is called diffuse reflection (Figure 28.10). If the surface is so smooth that the distances between successive elevations on the surface are less than about one-eighth the wavelength of the light, there is very little diffuse reflection, and the surface is said to be polished. A surface, therefore, may be polished for radiation of a long wavelength but not polished for light of a short wavelength. The wire-mesh "dish" shown in Figure 28.11 is very rough for light waves and so is hardly mirrorlike, but for long-wavelength radio waves, it is "polished" and therefore an excellent reflector. Reflection off the walls of your room is a good example of diffuse reflection. The light reflects back into the room but produces no mirror images. Unlike specular reflection, diffuse reflection does not produce a mirror image.
Describe color mixing by subtraction
When mixing paints, the color the end product will reflect is the color the only color they both reflect. The most useful subtractive colors for this are magenta, cyan, and yellow. if you add cyan and yellow pigments together they end product will reflect a green color because they both reflect green.
What causes total internal reflection to occur
When the flashlight is tipped beyond the critical angle (48° from the normal for water), you'll notice that all the light is reflected back into the tub. This is total internal reflection. The light striking the air-water surface obeys the law of reflection: The angle of incidence is equal to the angle of reflection. The only light emerging from the surface of the water is the light that is diffusely reflected from the bottom of the bathtub.
describe the conditions for resonance
You have to have forced vibrations on some something that match its natural frequency its natural frequency
continuous spectrum
a blended rainbow appearing spectrum with no breaks as viewed in a spectro scope
shock wave
a cone shaped wave produced by an object moving at supersonic speed through a fluid
sine curve
a curve whose shape represents the crests and troughs of a wave,
Schematic diagram
a graphical representation of a circuit that uses lines to represent wires and different symbols to represent components
Photon
a massless bundle of electromagnetic energy, A light particle
Fiber optics
a transparent fiber usually made of glass or plastic that can transmit light down its length using total internal reflection.
Distinguish between a transverse and a longitudinal wave
a transverse wave moves perpendicular to the direction to wave travel. examples of transverse waves are: - light - Electromagnetic waves - waves in the ocean A longitudinal wave moves parallel to the direction of wave travel. Examples of a lognitudnal wave are - sound -seismic p waves
Simple Harmonic Motion (SHM)
back and forth vibratory motion, for instance a pendulum or mass on a spring
examples of voltage sources
batteries and generators
Electrostatics
electricity at rest, the study if electric charges, the forces between them, and their behavior in materials
Electric power
equal to the product of current and voltage
equation for frequency
f=1/Period (T)
Total resistance
for series Rt= R1+R2+R3..... for parallel 1/Rt= 1/R1 +1/R2 + 1/R3 .........
explain charging by induction, charging by friction, and charging by contact
friction: Electrons can be transferred by rubbing two objects against each other. The item that loses electrons is positively charged. Contact: Electron transfer by two objects touching Induction: If you bring a charged object near a conducting surface, electrons are made to move in the surface material, even without physical contact. We see this in the two spheres example. if you bring a negatively charged rod near two touching neutral spheres, the sphere closest to the rod will become positively charged and the one farthest away will become negatively charged because opposite charges attract and liked charges repel. If you pull the spheres away from each other they will stay charged.
What happens when sunlight is put through a prism
it separates into all the colors of visible light (Roy G biv)
dual nature of light
light has properties of both particles and waves
Explain what is meant by polarization of light and how it shows that light waves are transverse
light waves are transverse and normally travel on all axis. But when light is polarized it blocks the light waves traveling on all axis except the one it lets through. (think of it like a gate with vertical iron bars, you can shake a rope vertically in the slits but not horizontally) You can tell if glasses are polarized if you rotate a polarized filter in front of them and at some point (where the filters are perpendicular) no or very little light gets through.
Why are some materials transparent or opaque to light or other EM waves?
opaque: Because the frequency of the waves matches the resonant frequency of the material. they vibrate the atoms so much it turns the energy into heat Instead of re-emitting the light, the atom term-201will instead turn it into heat. Transparent: At lower wave frequencies, such as those of visible light, electrons in the glass atoms are forced into vibration, but at lower amplitudes. The atoms hold the energy for a shorter time, with less chance of collision with neighboring atoms, and with less energy transformed into heat. The energy of vibrating electrons is reemitted as light
line spectrum
pattern of distinct lines of color on a field of black, corresponding to particular wavelengths, that are seen in a spectroscope.
Antinodes
points of maximum amplitude on a standing wave
Nucleus
positively charged center of an atom than houses the protons and neutrons
Compression
pulse of compressed air
EM spectrum
radio waves, microwaves, infrared, visible light, ultraviolet, x-rays, gamma rays
diffuse reflection
reflection of light from a rough surface
total internal reflection
the 100% reflection of light that strikes the boundary between two media at an angle greater than the critical angle
angle of incidence
the angle between the incident ray and the normal to the surface
Refraction
the change in direction of a wave as it crosses the boundary between two media in which the wave travels at different speeds.
potential difference (voltage)
the difference in electric potential energy (voltage) between two points. Free charge flows when there is a difference and will continue until both points reach a common potential.
wavelength
the distance between the crest of one wave and the crest of the next wave. Or the distance between successive identical parts of a wave
focal length
the distance from the center of a lens to the focal point
Charge
the fundamental electrical property to which the mutual attractions or repulsions between electrons or protons is attributed
principal axis
the line joining the centers of curvature of the surfaces of a lens
frequency
the number of events per time. Measured in Hertz (Hz) (or events per time) Inverse of period.
focal point
the point at which the light rays meet
Dispersion
the separation of light into colors arranged according to their frequency by interaction with a prism of diffraction grating. Happens because light of different frequencies move at different speeds in different transparent mediums.
Spectrum
the spread of colors seen when white light is passed through a prism or diffraction grating. Dispersion in a Prism Different frequencies of light travel at different speeds in transparent materials so they bend at different angles. The separation of light into colors arranged according to their frequency is called dispersion.
Period
the time required for one cycle
Define complimentary colors and give examples of pairs
two colors of light that can add to white (because they contain RGB) yellow (green and red) + blue = white Magenta (red and blue) + green = white Cyan + red = white
Velocity of waves
v=fλ velocity = frequency * wavelength