Question 1

How much energy is in an 89.7 MHz photon of FM-radiation?

Accepted Answer

A)  2.2 × 10−33 J 
B)  9.5 × 10−27 J 
C)  7.4 × 10−42 J 
D)  5.9 × 10−26 J 
E)  3.7 × 10−25 J 
A)  2.2 × 10−33 J 
B)  9.5 × 10−27 J 
C)  7.4 × 10−42 J 
D)  5.9 × 10−26 J 
E)  3.7 × 10−25 J

Question 2

A wave packet can represent a quantum particle because

Accepted Answer

A)  it has the localized nature of a particle. 
B)  the group velocity is identical to the speed of the particle. 
C)  the waves that compose the packet can show interference and diffraction. 
D)  of all of the above. 
E)  of only (a) and (b) above. 
A)  it has the localized nature of a particle. 
B)  the group velocity is identical to the speed of the particle. 
C)  the waves that compose the packet can show interference and diffraction. 
D)  of all of the above. 
E)  of only (a) and (b) above.

Question 3

Photoelectrons are ejected when monochromatic light shines on a freshly-prepared (oxide-free) sodium surface. In order to obtain the maximum increase in the number of electrons ejected per second, the experimenter needs to

Accepted Answer

A)  increase the frequency of the light. 
B)  increase the intensity of the light. 
C)  increase the area illuminated by the light. 
D)  do all of the above. 
E)  do only (b) and (c) above. 
A)  increase the frequency of the light. 
B)  increase the intensity of the light. 
C)  increase the area illuminated by the light. 
D)  do all of the above. 
E)  do only (b) and (c) above.

Question 4

A photon whose energy is 8.00 × 10−15 J is scattered off an electron at a 90° angle. What is the wavelength of the scattered wave?

Accepted Answer

A)  2.73 × 10−11 m 
B)  2.25 × 10−11 m 
C)  2.50 × 10−11 m 
D)  2.40 × 10−12 m 
E)  2.48 × 10−11 m 
A)  2.73 × 10−11 m 
B)  2.25 × 10−11 m 
C)  2.50 × 10−11 m 
D)  2.40 × 10−12 m 
E)  2.48 × 10−11 m

Question 5

The wavelength of a 45-kg teenager moving at 5 m/s on a skateboard is about

Accepted Answer

A)  5 × 10−37 m. 
B)  3 × 10−36 m. 
C)  7 × 10−34 m. 
D)  0.1 m. 
E)  5 m. 
A)  5 × 10−37 m. 
B)  3 × 10−36 m. 
C)  7 × 10−34 m. 
D)  0.1 m. 
E)  5 m.

Question 6

A neutron has a mass of 1.67 × 10−27 kg. Its de Broglie wavelength is 1.4 × 10−10 m. What is its kinetic energy (in eV)?

Accepted Answer

A)  4 
B)  0.4 
C)  0.04 
D)  40 
E)  0.08 
A)  4 
B)  0.4 
C)  0.04 
D)  40 
E)  0.08

Question 7

Your temperature is 98.6°F. Assuming your skin is a perfect radiator (ε = 1), determine the wavelength corresponding to the largest intensity (in μm).

Accepted Answer

A)  8.0 
B)  9.3 
C)  3.0 
D)  5.7 
E)  29.4 
A)  8.0 
B)  9.3 
C)  3.0 
D)  5.7 
E)  29.4

Question 8

An atomic level has a lifetime, τ, of   . What is the linewidth,   , of this level?

Accepted Answer

A) 
  
B) 
  
C) 
  
D) 
  
E) 
  
A) 
  
B) 
  
C) 
  
D) 
  
E)

Exam 40: Introduction to Quantum Physics

How much energy is in an 89.7 MHz photon of FM-radiation?

A wave packet can represent a quantum particle because

Photoelectrons are ejected when monochromatic light shines on a freshly-prepared (oxide-free) sodium surface. In order to obtain the maximum increase in the number of electrons ejected per second, the experimenter needs to

A photon whose energy is 8.00 × 10−15 J is scattered off an electron at a 90° angle. What is the wavelength of the scattered wave?

The wavelength of a 45-kg teenager moving at 5 m/s on a skateboard is about

A neutron has a mass of 1.67 × 10−27 kg. Its de Broglie wavelength is 1.4 × 10−10 m. What is its kinetic energy (in eV)?

Your temperature is 98.6°F. Assuming your skin is a perfect radiator (ε = 1), determine the wavelength corresponding to the largest intensity (in μm).

An atomic level has a lifetime, τ, of . What is the linewidth, , of this level?

Physics and Measurement

Motion in One Dimension

Vectors

Motion in Two Dimensions

The Laws of Motion

Circular Motion and Other Applications of Newtons Laws

Energy of a System

Conservation of Energy

Linear Momentum and Collisions

Rotation of a Rigid Object About a Fixed Axis

Angular Momentum

Static Equilibrium and Elasticity

Universal Gravitation

Fluid Mechanics

Oscillatory Motion

Wave Motion

Superposition and Standing Waves

Temperature

The First Law of Thermodynamics

The Kinetic Theory of Gases

Heat Engines, Entropy, and the Second Law of Thermodynamics

Electric Fields

Gausss Law

Electric Potential

Capacitance and Dielectrics

Current and Resistance

Direct-Current Circuits

Magnetic Fields

Sources of the Magnetic Field

Faradays Law

Inductance

Alternating-Current Circuits

Electromagnetic Waves

The Nature of Light and the Principles of Ray Optics

Image Formation

Wave Optics

Diffraction Patterns and Polarization

Relativity

Quantum Mechanics

Atomic Physics

Molecules and Solids

Nuclear Structure

Particle Physics and Cosmology

Filters

A photon whose energy is 8.00 × 10−¹⁵ J is scattered off an electron at a 90° angle. What is the wavelength of the scattered wave?

A neutron has a mass of 1.67 × 10−²⁷ kg. Its de Broglie wavelength is 1.4 × 10−¹⁰ m. What is its kinetic energy (in eV)?