Question 1

The frequency of light beam A is twice that of light beam B. The ratio EA/EB of photon energies is:

Accepted Answer

A)  1/2 
B)  1/4 
C)  1 
D)  2 
E)  4 
A)  1/2 
B)  1/4 
C)  1 
D)  2 
E)  4

Question 2

Which of the following electromagnetic radiations has photons with the greatest momentum?

Accepted Answer

A)  blue light 
B)  yellow light 
C)  x-rays 
D)  radio waves 
E)  microwaves 
A)  blue light 
B)  yellow light 
C)  x-rays 
D)  radio waves 
E)  microwaves

Question 3

The intensity of a light beam with a wavelength of 500 nm is 2000 W/m2. The photon flux (in number/m2 . s) is about:

Accepted Answer

A)  5 *1017 
B)  5 * 1019 
C)  5 * 1021 
D)  5 * 1023 
E)  5 * 1025 
A)  5 *1017 
B)  5 * 1019 
C)  5 * 1021 
D)  5 * 1023 
E)  5 * 1025

Question 4

Electromagnetic radiation with a wavelength of 5.7 * 10-12 m is incident on stationary electrons. Radiation that has a wavelength of 6.577 * 10-12 m is detected at a scattering angle of :

Accepted Answer

A)  10$\degree$ 
B)  121$\degree$ 
C)  40$\degree$ 
D)  50$\degree$ 
E)  69$\degree$ 
A)  10$\degree$ 
B)  121$\degree$ 
C)  40$\degree$ 
D)  50$\degree$ 
E)  69$\degree$

Question 5

An electron with energy E is incident upon a potential energy barrier of height Epot > E and thickness L. The transmission coefficient T:

Accepted Answer

A)  is zero 
B)  decreases exponentially with L 
C)  is proportional to 1/L 
D)  is proportional to 1/L2 
E)  is non-zero and independent of L 
A)  is zero 
B)  decreases exponentially with L 
C)  is proportional to 1/L 
D)  is proportional to 1/L2 
E)  is non-zero and independent of L

Question 6

Which of the following electromagnetic radiations has photons with the greatest energy?

Accepted Answer

A)  blue light 
B)  yellow light 
C)  x-rays 
D)  radio waves 
E)  microwaves 
A)  blue light 
B)  yellow light 
C)  x-rays 
D)  radio waves 
E)  microwaves

Question 7

The quantization of energy, E = nhf, is not important for an ordinary pendulum because:

Accepted Answer

A)  the formula applies only to mass-spring oscillators 
B)  the allowed energy levels are too closely spaced 
C)  the allowed energy levels are too widely spaced 
D)  the formula applies only to atoms 
E)  the value of h for a pendulum is too large 
A)  the formula applies only to mass-spring oscillators 
B)  the allowed energy levels are too closely spaced 
C)  the allowed energy levels are too widely spaced 
D)  the formula applies only to atoms 
E)  the value of h for a pendulum is too large

Question 8

The units of the Planck constant h are those of:

Accepted Answer

A)  energy 
B)  power 
C)  momentum 
D)  angular momentum 
E)  frequency 
A)  energy 
B)  power 
C)  momentum 
D)  angular momentum 
E)  frequency

Question 9

The work function for a certain sample is 2.3 eV. The stopping potential for electrons ejected from the sample by 7.0 *1014-Hz electromagnetic radiation is:

Accepted Answer

A)  0 
B)  0.60 V 
C)  2.3 V 
D)  2.9 V 
E)  5.2 V 
A)  0 
B)  0.60 V 
C)  2.3 V 
D)  2.9 V 
E)  5.2 V

Question 10

Monoenergetic electrons are incident on a single slit barrier. If the energy of each incident electron is increased the central maximum of the diffraction pattern:

Accepted Answer

A)  widens 
B)  narrows 
C)  stays the same width 
D)  widens for slow electrons and narrows for fast electrons 
E)  narrows for slow electrons and widens for fast electrons 
A)  widens 
B)  narrows 
C)  stays the same width 
D)  widens for slow electrons and narrows for fast electrons 
E)  narrows for slow electrons and widens for fast electrons

Question 11

Consider the following three particles:   Rank them according to the wavelengths of their waves, least to greatest.

Accepted Answer

A)  1, 2, 3 
B)  3, 2, 1 
C)  2, 3, 1 
D)  1, 3, 2 
E)  1, then 2 and 3 tied 
A)  1, 2, 3 
B)  3, 2, 1 
C)  2, 3, 1 
D)  1, 3, 2 
E)  1, then 2 and 3 tied

Question 12

Light beams A and B have the same intensity but the wavelength associated with beam A is longer than that associated with beam B. The photon flux (number crossing a unit area per unit time) is:

Accepted Answer

A)  greater for A than for B 
B)  greater for B than for A 
C)  the same for A and B 
D)  greater for A than for B only if both have short wavelengths 
E)  greater for B than for A only if both have short wavelengths 
A)  greater for A than for B 
B)  greater for B than for A 
C)  the same for A and B 
D)  greater for A than for B only if both have short wavelengths 
E)  greater for B than for A only if both have short wavelengths

Question 13

Evidence for the wave nature of matter is:

Accepted Answer

A)  electron diffraction experiments of Davisson and Germer 
B)  Thompson's measurement of e/m 
C)  Young's double slit experiment 
D)  the Compton effect 
E)  Lenz's law 
A)  electron diffraction experiments of Davisson and Germer 
B)  Thompson's measurement of e/m 
C)  Young's double slit experiment 
D)  the Compton effect 
E)  Lenz's law

Exam 38: Photons and Matter Waves

The frequency of light beam A is twice that of light beam B. The ratio EA/EB of photon energies is:

Which of the following electromagnetic radiations has photons with the greatest momentum?

The intensity of a light beam with a wavelength of 500 nm is 2000 W/m2. The photon flux (in number/m2 . s) is about:

Electromagnetic radiation with a wavelength of 5.7 * 10-12 m is incident on stationary electrons. Radiation that has a wavelength of 6.577 * 10-12 m is detected at a scattering angle of :

An electron with energy E is incident upon a potential energy barrier of height Epot > E and thickness L. The transmission coefficient T:

Which of the following electromagnetic radiations has photons with the greatest energy?

The quantization of energy, E = nhf, is not important for an ordinary pendulum because:

The units of the Planck constant h are those of:

The work function for a certain sample is 2.3 eV. The stopping potential for electrons ejected from the sample by 7.0 *1014-Hz electromagnetic radiation is:

Monoenergetic electrons are incident on a single slit barrier. If the energy of each incident electron is increased the central maximum of the diffraction pattern:

Consider the following three particles: Rank them according to the wavelengths of their waves, least to greatest.

Light beams A and B have the same intensity but the wavelength associated with beam A is longer than that associated with beam B. The photon flux (number crossing a unit area per unit time) is:

Evidence for the wave nature of matter is:

Measurement

Motion Along a Straight Line

Vector

Motion in Two and Three Dimensions

Force and Motion I

Force and Motion II

Kinetic Energy and Work

Potential Energy and Conservation of Energy

Center of Mass and Linear Momentum

Rotation

Rolling, Torque, and Angular Momentum

Equilibrium and Elasticity

Gravitation

Fluids

Oscillations

Waves I

Waves II

Temperature, Heat, and the First Law of Thermodynamics

The Kinetic Theory of Gases

Entropy and the Second Law of Thermodynamics

Electric Charge

Electric Fields

Gauss Law

Electric Potential

Capacitance

Current and Resistance

Circuits

Magnetic Fields

Magnetic Fields Due to Currents

Induction and Inductance

Electromagnetic Oscillations and Alternating Current

Maxwells Equations; Magnetism of Matter

Electromagnetic Waves

Images

Interference

Diffraction

Relativity

More About Matter Waves

All About Atoms

Conduction of Electricity in Solids

Nuclear Physics

Energy From the Nucleus

Quarks, Leptons, and the Big Bang

Filters

The frequency of light beam A is twice that of light beam B. The ratio E_A/E_B of photon energies is:

The intensity of a light beam with a wavelength of 500 nm is 2000 W/m². The photon flux (in number/m² . s) is about:

Electromagnetic radiation with a wavelength of 5.7 * 10^-¹² m is incident on stationary electrons. Radiation that has a wavelength of 6.577 * 10^-¹² m is detected at a scattering angle of :

An electron with energy E is incident upon a potential energy barrier of height E_pot > E and thickness L. The transmission coefficient T:

The work function for a certain sample is 2.3 eV. The stopping potential for electrons ejected from the sample by 7.0 *10¹⁴-Hz electromagnetic radiation is: