Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Physics > light and atoms > Flashcards

light and atoms Flashcards

1
Q

what creates an electromagnetic wave

A

the oscillation of an electron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

roughly show the visible light spectrum and the colors associated with there frequency

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

draw the wave diagram of a vertical and horizontally positioned antenna with axis labels

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is the definition of monochromatic light

A

mono chromatic light is light composed of a single frequency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is a coherent wave source

A

a coherent wave source is a wave source that is in phase and has the same frequency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

why is white light neither monochromatic or coherent

A

because white light is made up of lots of different colors of light it isn’t monochromatic and these are out of phase therefore not coherent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is required to have a good observable diffraction effect

A

the wavelength must be similar to the slit size

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is required to have a good observable diffraction effect

A

the wavelength must be similar to the slit size

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is diffraction

A

diffraction is the bending of a wave as it passes through an opening or around an obstacle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what does an intensity distribution of a diffraction grating glook like

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what formula would you use to find the maximum orders for a diffraction grating

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the photoelectric effect

A

the photoelectric effect is the emission of electrons when illuminated by light of high enough frequency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what effect does increasing the intensity but not the frequency have on the readings

A

there is a higher current detected

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what effect does increasing the frequency have on the readings

A

when the frequency is increased the kinetic energy is increased

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

how did Einstein explain the photo electric effect

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

draw a graph of ek max vs frequency label and explain all the intercepts and the slope and what happens if a metal with a higher threshold frequency is measured

A

the slope would be equal to planks constant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

how does an x-ray differ from a standard photoelectric effect

A

-they have a continuous range of frequency’s
-an x-ray is caused by accelerating an electron not a photon
-there are high intensity peaks at certain frequencies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

why does an x-ray have a continuous range of frequency’s

A

when an electron collides closer to the nucleus there is more energy as the path is changed by the electrostatic forces and the closer to the nucleus the more energy

18
Q

draw a graph and explain what happens to a intensity vs frequency graph for an x-ray when the current is increased, the voltage is increased or the target metal is changed

A
19
Q

what is attenuation

A

attenuation is the reduction in x-rays as they pass through a material due to the absorption or scattering of x-ray photons

20
Q

what can effect attenuation

A

-the thicker a material is the greater the attenuation
-the denser the material the less x-rays can pass through
-the greater the atomic number of a material the greater the attenuation

21
Q

what is the diffrence between hard and soft x-rays

A

a hard x-ray is used when doing things like chest or leg x-rays and have high photon energies and frequency’s
soft x-rays are used on things with low attenuation and will have relatively low photon energies and frequency’s

22
Q

what was de Broglie’s proposal

A

de Broglie proposed that moving particles have a wavelength that depends on there momentum

23
Q

what is the formula for de Broglie’s wave length

A

lambda= h/p

24
Q

how can line emission spectra be produced

A

by heating to high temperatures or placing a large potential diffrence through it

25
Q

how does the minimum work for a material relate to the different states

A

the eV diffrence from n=1 to n=infinity is equal to the minimum work required to release an electron

26
Q

what is the diffrence between a photon exiting an electron and another electron exciting an electron

A

when a photon excites an electron the energy level in the photon must be exactly equal to that of the diffrence between the state of the electron and another exited state. when an electron excites an electron it doesn’t have to be exact and as long as the energy of the incident electron is greater the diffrence it can transfer the energy and what ever is left pver is scattered

26
Q

what is the diffrence between a photon exiting an electron and another electron exciting an electron

A

when a photon excites an electron the energy level in the photon must be exactly equal to that of the diffrence between the state of the electron and another exited state.
when an electron excites an electron it doesn’t have to be exact and as long as the energy of the incident electron is greater the diffrence it can transfer the energy and what ever is left over is scattered

27
Q

how does the energy of the incident electron cause the peaks of an x-ray

A

when an incident electron of high enough energy collides with an electron in the ground shell it can knock it out of the atom. an electron from the next shell drops down causing an x-ray photon equal to the energy diffrence. this jump is often the pne with the largest potential diffrence therfore it causes the peaks

28
Q

what is the ground states also referred to as

A

K-shell

29
Q

what is n=2 also referred to as

A

L-shell

30
Q

what is n=3 also referred to as

A

M-shell

31
Q

explain the presence of absorption lines in the suns spectrum

A

the suns core creates a white light with a continuous range of frequencies. as the light passes through the atmosphere the temperature drops electrons within the cooler gasses then get exited by the suns photons and absorb them. removing them from the incident light

32
Q

what is fluorescence

A

fluorescence is the when an electron that is exited releases more than one photon as it reverts to ground state

33
Q

what is the diffrence between stimulated and spontaneous emission

A

spontaneous emission is when an electron is exited by a photon into a higher energy state and instantly returns to that state releasing one photon.
stimulated emission is when an electron in an exited state returns to a lower state because it is hit by an incident photon of the exact diffrence between the two states. this causes two photons to be emitted

34
Q

what is metastable state and population inversion

A

metastable is when an electron stays in an exited state longer than expected. population inversion is when there are more atoms in an exited state than a ground state

35
Q

what are the four fundamental forces

A

-electromagnetic
-weak nuclear
-strong nuclear
-gravitational

36
Q

what is a gauge boson and what are the four Gauge bosons with corresponding forces

A

electromagnetic - photon
weak nuclear - W, Z
Strong nuclear - gluon
gravitational - graviton

37
Q

describe the electromagnetic forces in terms of gauge bosons

A

a photon has an energy of E=hf. a photon emitted by one electron will cause a recoil. The closer the electron are the more energy they have.

38
Q

describe the weak nuclear forces in terms of gauge bosons

A

when neutrinos interact they they are mediated by exchange bosons of W and Z.

39
Q

describe the strong nuclear forces in terms of gauge bosons

A

the exchange of pions is what mediates the strong repulsive force between two protons. the exchange of pions between nucleons mediates the repulsive force.

40
Q

what is an anti particle

A

an anti particle has the same mass, spin and lifespan of the particle but a their charge has opposite signs

41
Q

what happens when an anti particle and a particle collide

A

they annihilat and release two photons in opposite directions. the energy released is in accordance with E=mc^2

Physics (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions