Question 1

When a current flows through an inductor, its mass

Accepted Answer

A)  decreases. 
B)  increases. 
C)  stays the same. 
D)  oscillates. 
A)  decreases. 
B)  increases. 
C)  stays the same. 
D)  oscillates. B

Question 2

Two satellites with equal rest masses of 100 kg are traveling toward each other in deep space. They have identical speeds of 0.600c. The satellites collide and stick together. What is the rest mass of the combined object after the collision?

Accepted Answer

A)  200 kg 
B)  225 kg 
C)  250 kg 
D)  275 kg 
E)  300 kg 
A)  200 kg 
B)  225 kg 
C)  250 kg 
D)  275 kg 
E)  300 kg C

Question 3

Astronaut Brian leaves Earth in a spaceship at a speed of 0.280c relative to an observer on Earth. Brian is holding a pencil at an angle of 30.0° with the direction of travel, as seen by Brian. What angle does the pencil make with the direction of travel, as seen in the frame of reference of the observer?

Accepted Answer

A)  29.0° 
B)  30.0° 
C)  31.0° 
D)  32.0° 
E)  33.0° 
A)  29.0° 
B)  30.0° 
C)  31.0° 
D)  32.0° 
E)  33.0° C

Question 4

Which of the following results shows the validity of the relativistic effect of time dilation?

Accepted Answer

A)  the detection of gravity waves 
B)  bending of light near the Sun 
C)  the decay of muons 
D)  red shift in distant galaxies 
E)  blue shift in distant galaxies 
A)  the detection of gravity waves 
B)  bending of light near the Sun 
C)  the decay of muons 
D)  red shift in distant galaxies 
E)  blue shift in distant galaxies

Question 5

The special theory of relativity sets a limit on speed. Does it set a limit on energy?

Accepted Answer

A)  Yes 
B)  No 
A)  Yes 
B)  No

Question 6

Two spaceships approach each other along a straight line at a constant velocity of 0.988c as measured by the captain of one of the ships. An observer on Earth is able to measure the speed of only one of the ships as 0.900c. From the point of view of the observer on Earth, what is the speed of the other ship?

Accepted Answer

The answer of Two spaceships approach each other along a...

Question 7

A one-kilogram gold ingot is carried from the bottom of the Eiffel tower to the top, 300 m above ground level. By what amount does its mass change?

Accepted Answer

A)  Its mass does not change. 
B)  Its mass increases by 3.27 × 10-14 kg. 
C)  Its mass decreases by 3.27 × 10-14 kg. 
D)  Its mass increases by 1.64 × 10-14 kg. 
E)  Its mass decreases by 1.64 × 10-14 kg. 
A)  Its mass does not change. 
B)  Its mass increases by 3.27 × 10-14 kg. 
C)  Its mass decreases by 3.27 × 10-14 kg. 
D)  Its mass increases by 1.64 × 10-14 kg. 
E)  Its mass decreases by 1.64 × 10-14 kg.

Question 8

What is the relativistic momentum of a 0.456-kg rest mass moving at 1.20 × 108 m/s?

Accepted Answer

A)  5.47 × 107 kg∙m/s 
B)  5.57 × 107 kg∙m/s 
C)  5.67 × 107 kg∙m/s 
D)  5.87 × 107 kg∙m/s 
E)  5.97 × 107 kg∙m/s 
A)  5.47 × 107 kg∙m/s 
B)  5.57 × 107 kg∙m/s 
C)  5.67 × 107 kg∙m/s 
D)  5.87 × 107 kg∙m/s 
E)  5.97 × 107 kg∙m/s

Question 9

What is meant by proper time?

Accepted Answer

Proper time is the a

Question 10

Observer A sees a ruler moving by in a relativistic train and measures its length to be LA. Observer B moves together with the train and measures the length of the ruler to be LB. These two results will be such that

Accepted Answer

A)  LA > LB. 
B)  LA = LB. 
C)  LA B. 
D)  LA could be greater or smaller than LB depending on the direction of the motion. 
A)  LA > LB. 
B)  LA = LB. 
C)  LA B. 
D)  LA could be greater or smaller than LB depending on the direction of the motion.

Question 11

What mass would have to be condensed to a radius of 1.0 × 10-15 m (the order of magnitude of the radius of an atomic nucleus) in order for it to become a black hole? G = 6.67 × 10-11 Nm2/kg2.

Accepted Answer

A)  1.1 × 10-6 kg 
B)  4.1 × 10-8 kg 
C)  2.2 × 103 kg 
D)  6.7 × 1011 kg 
E)  8.3 × 1015 kg 
A)  1.1 × 10-6 kg 
B)  4.1 × 10-8 kg 
C)  2.2 × 103 kg 
D)  6.7 × 1011 kg 
E)  8.3 × 1015 kg

Question 12

A muon at rest decays in 2.2 μs. Moving at 99.% the speed of light, it would be seen to "live" for how long?

Accepted Answer

The answer of A muon at rest decays in 2.2...

Question 13

Suppose one twin takes a ride in a space ship traveling at a very high speed to a distant star and back again, while the other twin remains on Earth. The twin that remained on Earth predicts that the astronaut twin is

Accepted Answer

A)  younger. 
B)  the same age. 
C)  older. 
D)  cannot be determined from the given information 
A)  younger. 
B)  the same age. 
C)  older. 
D)  cannot be determined from the given information

Question 14

Astronaut Jill leaves Earth in a spaceship and is now traveling at a speed of 0.280c relative to an observer on Earth. When Jill left Earth, the spaceship was equipped with all kinds of scientific instruments, including a meter stick. Now that Jill is underway, how long does she measure the meter stick to be?

Accepted Answer

A)  1.00 m 
B)  0.960 m 
C)  1.04 m 
D)  0.280 m 
E)  1.28 m 
A)  1.00 m 
B)  0.960 m 
C)  1.04 m 
D)  0.280 m 
E)  1.28 m

Question 15

You are moving at a speed (2/3)c relative to Randy, and Randy shines a light toward you. At what speed do you see the light passing you by?

Accepted Answer

A)  (1/3)c 
B)  (2/3)c 
C)  (4/3)c 
D)  c 
E)  It depends on whether you are moving towards or away from Randy. 
A)  (1/3)c 
B)  (2/3)c 
C)  (4/3)c 
D)  c 
E)  It depends on whether you are moving towards or away from Randy.

Question 16

Two satellites with equal rest masses are traveling toward each other in deep space. One is traveling at 0.550c and the other at 0.750c. The satellites collide and stick together. What is the speed of the combined object after the collision?

Accepted Answer

A)  0.100c 
B)  0.113c 
C)  0.150c 
D)  0.175c 
E)  0.311c 
A)  0.100c 
B)  0.113c 
C)  0.150c 
D)  0.175c 
E)  0.311c

Question 17

Einstein's theory of general relativity applies to gravitation.

Accepted Answer

A) True 
 B)False

Question 18

You are a passenger on a spaceship. As the speed of the spaceship increases, you would observe

Accepted Answer

A)  the length of your spaceship getting shorter. 
B)  the length of your spaceship getting longer. 
C)  the length of your spaceship varying erratically. 
D)  nothing unusual about the length of your spaceship. 
A)  the length of your spaceship getting shorter. 
B)  the length of your spaceship getting longer. 
C)  the length of your spaceship varying erratically. 
D)  nothing unusual about the length of your spaceship.

Question 19

A spaceship traveling at constant speed passes by Earth and later passes by Mars. In which frame of reference is the amount of time separating these two events the proper time?

Accepted Answer

A)  the Earth frame of reference 
B)  the Mars frame of reference 
C)  the spaceship frame of reference 
D)  any inertial frame of reference 
E)  any frame of reference, inertial or not 
A)  the Earth frame of reference 
B)  the Mars frame of reference 
C)  the spaceship frame of reference 
D)  any inertial frame of reference 
E)  any frame of reference, inertial or not

Question 20

An electron slowing from 0.998c to 0.500c loses how much momentum?
 Express the answer in MeV/c as well as N-s.

Accepted Answer

7.77 MeV/c

Exam 29: Relativity

When a current flows through an inductor, its mass

Two satellites with equal rest masses of 100 kg are traveling toward each other in deep space. They have identical speeds of 0.600c. The satellites collide and stick together. What is the rest mass of the combined object after the collision?

Which of the following results shows the validity of the relativistic effect of time dilation?

The special theory of relativity sets a limit on speed. Does it set a limit on energy?

A one-kilogram gold ingot is carried from the bottom of the Eiffel tower to the top, 300 m above ground level. By what amount does its mass change?

What is the relativistic momentum of a 0.456-kg rest mass moving at 1.20 × 108 m/s?

What is meant by proper time?

Observer A sees a ruler moving by in a relativistic train and measures its length to be LA. Observer B moves together with the train and measures the length of the ruler to be LB. These two results will be such that

What mass would have to be condensed to a radius of 1.0 × 10-15 m (the order of magnitude of the radius of an atomic nucleus) in order for it to become a black hole? G = 6.67 × 10-11 Nm2/kg2.

A muon at rest decays in 2.2 μs. Moving at 99.% the speed of light, it would be seen to "live" for how long?

Suppose one twin takes a ride in a space ship traveling at a very high speed to a distant star and back again, while the other twin remains on Earth. The twin that remained on Earth predicts that the astronaut twin is

You are moving at a speed (2/3)c relative to Randy, and Randy shines a light toward you. At what speed do you see the light passing you by?

Two satellites with equal rest masses are traveling toward each other in deep space. One is traveling at 0.550c and the other at 0.750c. The satellites collide and stick together. What is the speed of the combined object after the collision?

Einstein's theory of general relativity applies to gravitation.

You are a passenger on a spaceship. As the speed of the spaceship increases, you would observe

A spaceship traveling at constant speed passes by Earth and later passes by Mars. In which frame of reference is the amount of time separating these two events the proper time?

An electron slowing from 0.998c to 0.500c loses how much momentum? Express the answer in MeV/c as well as N-s.

Introduction to Physics

One-Dimensional Kinematics

Vectors in Physics

Two-Dimensional Kinematics

Newtons Laws of Motion

Applications of Newtons Laws

Work and Kinetic Energy

Potential Energy and Conservation of Energy

Linear Momentum and Collisions

Rotational Kinematics and Energy

Rotational Dynamics and Static Equilibrium

Gravity

Oscillations About Equilibrium

Waves and Sound

Fluids

Temperature and Heat

Phases and Phase Changes

The Laws of Thermodynamics

Electric Charges, Forces, and Fields

Electric Potential and Electric Potential Energy

Electric Current and Direct-Current Circuits

Magnetism

Magnetic Flux and Faradays Law of Induction

Alternating-Current Circuits

Electromagnetic Waves

Geometrical Optics

Optical Instruments

Physical Optics: Interference and Diffraction

Quantum Physics

Atomic Physics

Nuclear Physics and Nuclear Radiation

Filters

What is the relativistic momentum of a 0.456-kg rest mass moving at 1.20 × 10⁸ m/s?

Observer A sees a ruler moving by in a relativistic train and measures its length to be L_A. Observer B moves together with the train and measures the length of the ruler to be L_B. These two results will be such that

What mass would have to be condensed to a radius of 1.0 × 10^-15 m (the order of magnitude of the radius of an atomic nucleus) in order for it to become a black hole? G = 6.67 × 10^-11 Nm²/kg².