ISCI exam 2 in depth study guide
facts about observers and reference frames
- an observer sees her own reference frame as stationary -two objects that are moving at the same velocity compared to an observer could be in the same reference frame
How is molecular motion increased
-absorbing energy -adding heat through a temperature difference
places where light of the same wavelength from two sources would interfere constructively include
-at a location where light from one source travels two wavelengths farther from the other -at a location where the troughs of both waves arrive at the same time -at a location where the peaks of the two waves arrive simultaneously
Entropy
-disorderly -random -lacks pattern
releases energy
-freezing -condensation
air is a good insulator because
-gas does not transfer heat well bc molecules are far apart -conduction takes place slowly in a gas -gas molecules are not attached to each other
how can an object become electrostatically charged
-induction -friction -contact
plasma can
-interact strongly with magnetic fields -conduct electricity
key features of the light ray model include
-light travels in straight lines -light can be absorbed -light changes direction as it enters and exits materials with different properties
a food calorie is
-measure of the chemical energy released by the oxidation of food -equivalent to 1,000 calories -same as a kilocalorie
The laws of thermodynamics are concerned with relationships between which of the following items
-mechanical energy -heat -work
absorbs energy
-melting -evaporation -sublimation
Select all the statements that are true regarding the charge of protons and electrons
-protons have a positive charge -the charge of protons and electrons is opposite -Electrons and protons cannot be separated from their charge
what two factors influence the size of the electrostatic force between two charged objects
-the distance between them -the amount of charge on each object
how can you measure electric potential difference
-the work that the charge can do because of its position -by the work that is done to move the charge
To determine how much________ is needed to change the sate of an object you need to know the starting temperature, the mass and the nature
Heat
___________ an object increases its internal energy
Heating
Is a kWh a unit of power or a unit of work?
It is a unit of work since W=Pt (from P=W/t)
Celsius
Water freezes at 0 degrees and boils at 100
Farenheit
Water freezes at 32 degrees and boils at 212
planck's constant
a conversion to relate the frequency of light to the amount of energy in a photon
the photoelectric effect is explained by
a particle model
photon
a single quantum of energy in the form of light
quantum
a tiny,finite,discrete amount
________________ is the attractive force between different kinds of molecules
adhesion
Substances that have magnetic properties( ferromagnetic properties) are ones that ______
are strongly attracted to magnets
Radiation is a type of heat energy transfer that occurs between two objects _______________
as long as there is a temperature diff between the two
how are a sodium atom and a sodium ion alike
atomic number
number of protons
atomic number
Temperature is based on the _______ molecular kinetic energy of a body
average
the information- carrying capacity of a transmission medium, such as a fiber optics cable is its_______________
bandwidth
_______________ radiation is produced by incandescent light sources
blackbody
what is similar about the bohr model of the atom and the quantum mechanics model
both consider electrons to emit a photon when moving from a higher state to a lower state
______________ is the attractive force between the same kind of molecules
cohesion
the light can be made to focus on the retina by using a _________ to ____________ the light rays before they enter the eye
convex, converge
the metric quantity of electric charge is measured in
coulumbs
what is the difference between ac and dc
dc moves in one direction and ac moves back and forth
The magnetic ____________ is the angle of the magnetic field between the horizontal and the downward angle of compassion needle that is free to pivot
dip
The electric current moves in one direction in an _________ current and switches back and forth in an ________________ current
direct, alternating
In the production of light by an incandescent source, internal heat moves particles that make up the glowing object. The moving nuclei and electrons_____________________
disturb the electric and magnetic fields in the material, creating electromagnetic radiation
an electric motor works by converting_________energy to _________energy
electrical, mechanical
Static electricity involves the gain or loss of _________ from an object; these particles do not leave the object until there is a discharge
electrons
greek word for amber
electrons
why do the energies of electrons in an atom have negative values
electrons have zero potential energy when they are free from an atom
how do you know that it is an electric field
electrons in an active circuit either drift slowly or just jiggle back and forth in one place
main problem with a solar system model of the atom
electrons moving in a circle would be accel, lose energy and would not be able to maintain their orbits
The two magnetic poles of a magnet are where the _____
forces of attraction seem concentrated
the speed of light is equal to the product of the wave's __________ and __________
frequency and wavelength
solid liquid phase change is called the latent heat of ________
fusion
a ____________ measures electric currents by measuring magnetic fields they produce
galvanometer
in Einstein's ___________ theory of relativity, gravity is understood to be the result of mass warping the structure of four- dimensional spacetime
general
magnetic declination is the angle diff between
geographic north pole and the magnetic north pole
what is the diff between a hydrogen atom in the ground vs one in an excited state
ground state has electrons in lowest possible energy state; excited states have higher energies
This is a measure of the internal energy that has been absorbed or transferred from one object to another
heat
gamma rays
highest frequency
what conditions are necessary for two light waves to form an interference pattern of right line and dark areas
in phase light waves travel different distances from two slits to a screen
materials become less dense as their temp increases because
increased energy results in molecules moving farther apart
the total kinetic and potential energy is known as
internal energy
ionic vs covalent electrons
ionic are transferred covalent are shared
is sodium fluoride ionic, covalent or polar covalent
ionic because the difference in electronegativity is 3.1
how does an electric generator generate an electric current
it does work in moving electrons, which creates an electric field
The __________ molecular theory is a summary of the scientific assumptions about molecules and the space around them
kinetic
an animal that is bioluminous can produce its own
light
light is best summarized by which of the following statements
light exhibits characteristics of waves and particles and either model may be appropriate for a given situation
microwaves radiation
lowest frequency
The _________ number of an atom is the sum of its protons and _______
mass, neutrons
what experimental evidence led rutherford to the concept of a nucleus in an atom
massive particles are deflected at very large angles or straight back when directed at a very thin sheet of gold foil
cooler air is denser than warmer air and flows downhill because
molecules of cool air are able to move closer together
is the mass of an isotope a whole number
no, it is the relative mass of an isotope compared to carbon-12
how are a sodium atom and a sodium ion different
number of electrons
polarized light is explained
only by a wave model
reflection
outgoing waves are arranged more or less horizontally with a surface
A _________ ___________ occurs when a solid, liquid. or gas transitions from one phase to another
phase change
what is the diff between polar and nonpolar covalent bonds
polar electrons are shared unequally, nonpolar are shared equally
The silvered wall of a vacuum bottle takes care of heat flow by
radiation
a ________ uses a low voltage control to switch a larger, high voltage circuit on and off
relay
x-rays
second highest frequency
infrared light
second lowest frequency
why does total internal reflection occur more in a diamond than in other gemstones
small critical angle
selective absorption
small particles absorb and radiate light polarized with their directions of vibration
scattering
small particles absorb and reradiate light polarized with their directions of vibration
a measure of the average kinetic energy of the molecules making up a substance is
temperature
the color difference in stars is a result of the relationship between the color and the
temperature
what determines if an electromagnetic wave emitted from an object is a visible light wave or a wave of infrared radiation
the energy available for accelerating charged particles determines this
on a molecular level- how does the condensation of water vapor on a bathroom mirror warm the bathroom
the latent heat is released during vapor to liquid phase change
while the word temperature is used to describe how hot or cold something is, in terms of the kinetic molecular theory, temperature is
the measure of the average kinetic energy of the molecules in a substance
intensity
the number of photons emitted by a light source
frequency
the property that determines the energy of individual photons
conduction is a transfer of energy that occurs
through the interaction of molecules
an electromagnet can be produced by passing a current________-
through the wires of a solenoid
a device used to step up or step down the ac voltage in a circuit is called a _____________________
transformer
heat involved in a liquid-gas phase change (evaporation or condensation) is called the latent heat of __________________
vaporization
measure of electric potential difference between two points is
volt
Kelvin
water freezes at 273 and boils at 373
what is happening when you walk across a carpet and receive as hock when you touch a metal object
your body is a poor conductor and you accumulate electrons until they are conducted away by a metal object