Question 1

At what speed is the momentum of an object five times that found classically?

Accepted Answer

A) 0.894c 
B) 0.960c 
C) 0.980c 
D) 0.800c 
E) ​0.999c 
A) 0.894c 
B) 0.960c 
C) 0.980c 
D) 0.800c 
E) ​0.999c

Question 2

A nuclear reaction,which gives off a total of 1.2 × 1017 J of energy,expends how much mass in the process? (c = 3.00 × 108 m/s)

Accepted Answer

A) 0.1 kg 
B) 1.3 kg 
C) 4.0 kg 
D) 13.3 kg 
E) ​7.5 kg 
A) 0.1 kg 
B) 1.3 kg 
C) 4.0 kg 
D) 13.3 kg 
E) ​7.5 kg

Question 3

What is proper time?

Accepted Answer

A) Proper time is the time measured by a clock at rest with respect to the observer. 
B) Proper time is time based on your actual longitude,not your time zone. 
C) Proper time is the time given on your GPS. 
D) Proper time means standard time as opposed to daylight savings time. 
A) Proper time is the time measured by a clock at rest with respect to the observer. 
B) Proper time is time based on your actual longitude,not your time zone. 
C) Proper time is the time given on your GPS. 
D) Proper time means standard time as opposed to daylight savings time.

Question 4

Doubling the momentum of

Accepted Answer

A) a particle doubles its relativistic total energy. 
B) a particle quadruples its relativistic total energy. 
C) a photon doubles its relativistic total energy. 
D) a photon quadruples its relativistic total energy. 
A) a particle doubles its relativistic total energy. 
B) a particle quadruples its relativistic total energy. 
C) a photon doubles its relativistic total energy. 
D) a photon quadruples its relativistic total energy.

Question 5

An electron of mass 9.11 × 10−31 kg moves with a speed of 0.790c.What is its momentum? (c = 3.00 × 108 m/s)

Accepted Answer

A) 1.17E-22 kg⋅m/s 
B) 3.52E-22 kg⋅m/s 
C) 2.16E-22 kg⋅m/s 
D) 1.32E-22 kg⋅m/s 
E) ​2.73E-22 kg·m/s 
A) 1.17E-22 kg⋅m/s 
B) 3.52E-22 kg⋅m/s 
C) 2.16E-22 kg⋅m/s 
D) 1.32E-22 kg⋅m/s 
E) ​2.73E-22 kg·m/s

Question 6

From a stationary position,I observe a moving boxcar,which has a mirror along the front wall,but it is open at the back of the boxcar.I send a flash of light from my flashlight and time the flash of light as it goes to the front of the boxcar and returns to the back of the boxcar.A passenger in the boxcar also times the round trip of the flash of light.Compare the times recorded on our watches.

Accepted Answer

A) The time recorded on his watch is longer. 
B) The time recorded on the two watches is the same. 
C) The time recorded on his watch is shorter. 
D) The answer depends on the reference system you are in. 
A) The time recorded on his watch is longer. 
B) The time recorded on the two watches is the same. 
C) The time recorded on his watch is shorter. 
D) The answer depends on the reference system you are in.

Question 7

Relativity dealing with gravitation is known as:

Accepted Answer

A) inertial relativity. 
B) gravitational relativity. 
C) Galilean relativity. 
D) general relativity. 
A) inertial relativity. 
B) gravitational relativity. 
C) Galilean relativity. 
D) general relativity.

Question 8

At what speed would a clock have to be moving in order to run at a rate that is one-fourth the rate of a clock at rest?

Accepted Answer

A) 0.87c 
B) 0.75c 
C) 0.97​c​ 
D) 0.50c 
E) ​0.26c 
A) 0.87c 
B) 0.75c 
C) 0.97​c​ 
D) 0.50c 
E) ​0.26c

Question 9

The experiment that dispelled the idea that light travels in the ether is called the

Accepted Answer

A) Michelson-Morley experiment. 
B) Hafele and Keating experiment. 
C) Fitzgerald-Kennedy experiment. 
D) twin paradox. 
A) Michelson-Morley experiment. 
B) Hafele and Keating experiment. 
C) Fitzgerald-Kennedy experiment. 
D) twin paradox.

Question 10

An unknown particle in an accelerator moving at a speed of 1.50 × 108 m/s has a measured total energy of 3.30 × 10−9 J.What is its mass? (c = 3.00 × 108 m/s)

Accepted Answer

A) 4.23E-26 kg 
B) 9.17E-27 kg 
C) 7.78E-26 kg 
D) 3.18E-26 kg 
E) ​3.67E-26 kg 
A) 4.23E-26 kg 
B) 9.17E-27 kg 
C) 7.78E-26 kg 
D) 3.18E-26 kg 
E) ​3.67E-26 kg

Question 11

The Michelson-Morley experiment was designed to make use of ________ to find the motion of the Earth relative to the luminiferous ether.

Accepted Answer

A) sound waves 
B) interference fringes 
C) electromagnetic wind 
D) none of the above 
A) sound waves 
B) interference fringes 
C) electromagnetic wind 
D) none of the above

Question 12

Which characterizes the main result of the Michelson-Morley experiment?

Accepted Answer

A) verified the existence of ether 
B) involved measuring the speed of sound from a moving source 
C) detected no difference in the speed of light regardless of speed of the source relative to observer 
D) was designed purposely to verify Einstein's theory of relativity 
A) verified the existence of ether 
B) involved measuring the speed of sound from a moving source 
C) detected no difference in the speed of light regardless of speed of the source relative to observer 
D) was designed purposely to verify Einstein's theory of relativity

Question 13

A mass is bouncing on the end of a spring with a period T when measured by a ground observer.What would the period of oscillation be (as measured by the same observer)if the mass and spring were moving past the ground observer at a speed of 0.9c?

Accepted Answer

A) 5.3 T 
B) 0.40 T 
C) 3.2 T 
D) 2.3 T 
E) ​1.1 T 
A) 5.3 T 
B) 0.40 T 
C) 3.2 T 
D) 2.3 T 
E) ​1.1 T

Exam 26: Relativity

At what speed is the momentum of an object five times that found classically?

A nuclear reaction,which gives off a total of 1.2 × 1017 J of energy,expends how much mass in the process? (c = 3.00 × 108 m/s)

What is proper time?

Doubling the momentum of

An electron of mass 9.11 × 10−31 kg moves with a speed of 0.790c.What is its momentum? (c = 3.00 × 108 m/s)

Relativity dealing with gravitation is known as:

At what speed would a clock have to be moving in order to run at a rate that is one-fourth the rate of a clock at rest?

The experiment that dispelled the idea that light travels in the ether is called the

An unknown particle in an accelerator moving at a speed of 1.50 × 108 m/s has a measured total energy of 3.30 × 10−9 J.What is its mass? (c = 3.00 × 108 m/s)

The Michelson-Morley experiment was designed to make use of ________ to find the motion of the Earth relative to the luminiferous ether.

Which characterizes the main result of the Michelson-Morley experiment?

A mass is bouncing on the end of a spring with a period T when measured by a ground observer.What would the period of oscillation be (as measured by the same observer)if the mass and spring were moving past the ground observer at a speed of 0.9c?

Units, Trigonometry, and Vectors

Motion in One Dimension

Motion in Two Dimensions

Newtons Laws of Motion

Energy

Momentum, Impulse, and Collisions

Rotational Motion and Gravitation

Rotational Equilibrium and Dynamics

Fluids and Solids

Thermal Physics

Energy in Thermal Processes

The Laws of Thermodynamics

Vibrations and Waves

Sound

Electric Forces and Fields

Electrical Energy and Capacitance

Current and Resistance

Direct-Current Circuits

Magnetism

Induced Voltages and Inductance

Alternating-Current Circuits and Electromagnetic Waves

Reflection and Refraction of Light

Mirrors and Lenses

Wave Optics

Optical Instruments

Quantum Physics

Atomic Physics

Nuclear Physics

Nuclear Energy and Elementary Particles

Filters

A nuclear reaction,which gives off a total of 1.2 × 10¹⁷ J of energy,expends how much mass in the process? (c = 3.00 × 10⁸ m/s)

An electron of mass 9.11 × 10−³¹ kg moves with a speed of 0.790c.What is its momentum? (c = 3.00 × 10⁸ m/s)

An unknown particle in an accelerator moving at a speed of 1.50 × 10⁸ m/s has a measured total energy of 3.30 × 10−⁹ J.What is its mass? (c = 3.00 × 10⁸ m/s)