Units 24-28

Question 1

Energy Levels

Answer 1

the orbitals electrons move in

-quantized energy levels

Question 2

Bohr Model of the Atom

Answer 2

describes the electron as orbiting at a set of discrete radii

Question 3

Energy of Hydrogen eq

Answer 3

En=(-2.180 x 10^-18 J)/n^2

Question 4

Emission line spectrum

Answer 4

the different light emission from a hot gas, containing different x
unique to elements

Question 5

Balmer Lines

Answer 5

transitions between n=2 energy levels and higher levels

Question 6

Continuous spectrum

Answer 6

atoms must be packed so that electron energy levels are altered so each atom can interact with photons of different energies therefore allowing photons of all lambda to be emitted

Question 7

emission line spectrum

Answer 7

isolated atoms and molecules emit light only at certain wavelengths
produced by hot low density gas

Question 8

absorption line spectrum

Answer 8

produced when light from a hot dense body passes through cooler gas. All colors are present but light at certain wavelengths is missing

Question 9

radial velocity

Answer 9

an object moving directly away from us

Question 10

Doppler formula

Answer 10

Vr=( delta lambda/lambda) x c

Question 11

Redshifts

Answer 11

longer wavelength

Question 12

Blueshifts

Answer 12

Shorter wavelength

Question 13

Doppler Broadening

Answer 13

if atoms in a gas are moving, spectral lines will be spread over a wider range of wavelengths

Question 14

Rest frame

Answer 14

A coordinate system tied to the solar system’s position and motion in which it appears we are at rest

Question 15

Galilean relativity

Answer 15

how motions add to and subtract from one another

motions depend on rest frame

Question 16

Aether

Answer 16

scientists believed this substance existed, through which light waves always traveled at the same speed

Question 17

Lorentz factor

Answer 17

hypothesizes that an object’s length shortens in the direction in which it is moving by a factor equal to
gamma= 1/root((1-v^2)/c^2)

Question 18

Twin paradox

Answer 18

it seems as though the astronaut twin and the earth twin should each age slowly from the other’s point of view
astronaut would actually be aging slower

Question 19

free fall

Answer 19

when no forces resist motion in a gravitational field

Question 20

principle of equivalence

Answer 20

idea that gravity has the same effect on an object as being in an accelerating frame of reference
-an observer in freefall measures time normally so stationary clocks on the tower must be running slower

Question 21

Gravitational lensing

Answer 21

deflections can sometimes focus and brighten the light from a backgrounded object
allows astronomers to detect objects that may not be visible

Question 22

curvature of space

Answer 22

produced by mass and energy

Question 23

gravitational time dilation

Answer 23

tells us how much slower clocks run in a gravitational field based on Vesc

Question 24

Gravitational waves

Answer 24

when one object orbits another the motion of the two objects generate gravitational waves

Question 25

CCD

Answer 25

charge coupled device
when struck by a photon, electrons are free to move within the material
divided into pixels, number of electrons in each pixel generates an image

Question 26

photoelectric effect

Answer 26

in which a photon has sufficient energy causes an electron to become unbound from the atom its orbiting