Question 1

An oxygen-15 nucleus,  
O,decays to another atomic nucleus by emitting a β+ ray.What is the other atomic nucleus?

Accepted Answer

A)    N 
B)    F 
C)    C 
D)    C 
E)    N 
A)    N 
B)    F 
C)    C 
D)    C 
E)    N

Question 2

Uranium-238 decays into thorium-234 plus an alpha particle.The known masses are  
He: 4.002603 u  
Th: 234.043583 u  
U: 238.050786 u
How much energy is released in this process? (1 u = 931.5 MeV/c2)

Accepted Answer

A) 4.28 MeV 
B) 3.76 MeV 
C) 3.18 MeV 
D) 2.89 MeV 
E) 5.05 MeV 
A) 4.28 MeV 
B) 3.76 MeV 
C) 3.18 MeV 
D) 2.89 MeV 
E) 5.05 MeV

Question 3

Consider the nuclear reaction  
N +  
He →  
O +  
H.The known atomic masses are  
N: 14.003074 u  
He: 4.002603 u  
H: 1.007825 u  
O: 16.999131 u
What is the Q-value (or reaction energy)of this reaction? (1 u = 931.5 MeV/c2)

Accepted Answer

A) -1.191 MeV 
B) -2.020 MeV 
C) -6.725 MeV 
D) -9.055 MeV 
A) -1.191 MeV 
B) -2.020 MeV 
C) -6.725 MeV 
D) -9.055 MeV

Question 4

A radioactive substance with a half-life of 3.0 days has an initial activity of 2400 Bq.What is its activity after 6.0 days?

Accepted Answer

A) 1200 Bq 
B) 1800 Bq 
C) 600 Bq 
D) 300 Bq 
E) 150 Bq 
A) 1200 Bq 
B) 1800 Bq 
C) 600 Bq 
D) 300 Bq 
E) 150 Bq

Question 5

The diameter of an atom is 1.4 × 10-10 m and the diameter of its nucleus is 1.0 × 10-14 m.What fraction of the atom's volume is occupied by its nucleus?

Accepted Answer

A) 3.6 × 10-13 
B) 7.1 × 10-5 
C) 5.1 × 10-9 
D) 2.6 × 10-17 
A) 3.6 × 10-13 
B) 7.1 × 10-5 
C) 5.1 × 10-9 
D) 2.6 × 10-17

Question 6

How long will it take a 4.50-kBq sample of material to reach an activity level of 0.140 kBq if the half-life of the sample is 435 years?

Accepted Answer

A) 14,478 years 
B) 3245 years 
C) 2178 years 
D) 1993 years 
A) 14,478 years 
B) 3245 years 
C) 2178 years 
D) 1993 years

Question 7

A fusion reaction releases energy because the binding energy of the resulting nucleus

Accepted Answer

A) is greater than the binding energy of the original nuclei. 
B) is equal to the binding energy of the original nuclei. 
C) is less than the binding energy of the original nuclei. 
D) is released in the process. 
E) is absorbed in the process. 
A) is greater than the binding energy of the original nuclei. 
B) is equal to the binding energy of the original nuclei. 
C) is less than the binding energy of the original nuclei. 
D) is released in the process. 
E) is absorbed in the process.

Question 8

The maximum permissible workday dose for occupational exposure to radiation is 11 mrem.A 77-kg laboratory technician absorbs 2.3 mJ of 0.5-MeV gamma rays in a work day.The relative biological effectiveness (RBE)for gamma rays is 1.00.What is the number of gamma-ray photons absorbed by the technician in a workday?

Accepted Answer

A) 3 × 1010 
B) 3 × 109 
C) 3 × 108 
D) 1 × 109 
E) 1 × 108 
A) 3 × 1010 
B) 3 × 109 
C) 3 × 108 
D) 1 × 109 
E) 1 × 108

Question 9

The atomic number and mass number for calcium-39 are 20 and 39,respectively.How many neutrons are in one atom?

Accepted Answer

A) 1 
B) 19 
C) 20 
D) 39 
E) 59 
A) 1 
B) 19 
C) 20 
D) 39 
E) 59

Question 10

If a 2.0-MeV neutron released in a fission reaction loses half its kinetic energy in each moderator collision,how many collisions are needed to reduce its kinetic energy to 1/25 eV?

Accepted Answer

A) 6 
B) 18 
C) 26 
D) 30 
E) 4 
A) 6 
B) 18 
C) 26 
D) 30 
E) 4

Question 11

When a β- particle is emitted from an unstable nucleus,the atomic number of the nucleus

Accepted Answer

A) increases by 1. 
B) decreases by 1. 
C) increases by 2. 
D) decreases by 2. 
E) does not change. 
A) increases by 1. 
B) decreases by 1. 
C) increases by 2. 
D) decreases by 2. 
E) does not change.

Question 12

A β- decay occurs in an unstable nucleus when

Accepted Answer

A) a proton is converted to an electron by the strong force. 
B) a proton is converted to a neutron by the strong force. 
C) a neutron is converted to a proton by the weak force. 
D) a neutron is converted to an alpha particle by the weak force. 
E) a neutron is converted to a positron by the weak force. 
A) a proton is converted to an electron by the strong force. 
B) a proton is converted to a neutron by the strong force. 
C) a neutron is converted to a proton by the weak force. 
D) a neutron is converted to an alpha particle by the weak force. 
E) a neutron is converted to a positron by the weak force.

Question 13

The atom  
Fr decays to  
Ra by emitting what kind of nuclear radiation?

Accepted Answer

A) alpha 
B) beta-minus 
C) beta-plus 
D) gamma 
E) x-rays. 
A) alpha 
B) beta-minus 
C) beta-plus 
D) gamma 
E) x-rays.

Question 14

In the fission reaction 235U + 1n → 141Ba + 92Kr + x 1n,what is the number x of neutrons produced?

Accepted Answer

A) 0 
B) 1 
C) 2 
D) 3 
A) 0 
B) 1 
C) 2 
D) 3

Question 15

Two radioactive isotopes,X and Y,both decay to stable products.The half-life of X is about a day,while that of Y is about a week.Suppose a radioactive sample consists of a mixture of these two nuclides.If the mixture is such that the activities arising from X and Y are initially equal,then a few days later the activity of the sample will be due

Accepted Answer

A) predominantly to Y. 
B) predominantly to X. 
C) entirely to Y. 
D) to X and Y equally. 
A) predominantly to Y. 
B) predominantly to X. 
C) entirely to Y. 
D) to X and Y equally.

Question 16

In a laboratory accident,a work area is contaminated with radioactive material.Health physicists monitor the area during a 30-day period and obtain the data shown in the table.The accident occurred at time t = 0 days.They determine that it will not be safe for workers to enter the area until the radioactivity level has dropped to 16 counts per minute.Of the choices listed,which one is the earliest time after the accident that workers could safely return?

Accepted Answer

A) 77 days 
B) 90 days 
C) 102 days 
D) 65 days 
E) 48 days 
A) 77 days 
B) 90 days 
C) 102 days 
D) 65 days 
E) 48 days

Question 17

Today,uranium contains  
 
(half-life = 0.70 billion years)and  
 
(half-life = 4.5 billion years).At a time 1.9 billion years ago,what was the fraction of  
In uranium?

Accepted Answer

A) 3.53% 
B) 4.72% 
C) 4.90% 
D) 6.76% 
A) 3.53% 
B) 4.72% 
C) 4.90% 
D) 6.76%

Exam 32: Nuclear Physics and Nuclear Radiation

An oxygen-15 nucleus, O,decays to another atomic nucleus by emitting a β+ ray.What is the other atomic nucleus?

Uranium-238 decays into thorium-234 plus an alpha particle.The known masses are He: 4.002603 u Th: 234.043583 u U: 238.050786 u How much energy is released in this process? (1 u = 931.5 MeV/c2)

Consider the nuclear reaction N + He → O + H.The known atomic masses are N: 14.003074 u He: 4.002603 u H: 1.007825 u O: 16.999131 u What is the Q-value (or reaction energy)of this reaction? (1 u = 931.5 MeV/c2)

A radioactive substance with a half-life of 3.0 days has an initial activity of 2400 Bq.What is its activity after 6.0 days?

The diameter of an atom is 1.4 × 10-10 m and the diameter of its nucleus is 1.0 × 10-14 m.What fraction of the atom's volume is occupied by its nucleus?

How long will it take a 4.50-kBq sample of material to reach an activity level of 0.140 kBq if the half-life of the sample is 435 years?

A fusion reaction releases energy because the binding energy of the resulting nucleus

The atomic number and mass number for calcium-39 are 20 and 39,respectively.How many neutrons are in one atom?

If a 2.0-MeV neutron released in a fission reaction loses half its kinetic energy in each moderator collision,how many collisions are needed to reduce its kinetic energy to 1/25 eV?

When a β- particle is emitted from an unstable nucleus,the atomic number of the nucleus

A β- decay occurs in an unstable nucleus when

The atom Fr decays to Ra by emitting what kind of nuclear radiation?

In the fission reaction 235U + 1n → 141Ba + 92Kr + x 1n,what is the number x of neutrons produced?

Today,uranium contains (half-life = 0.70 billion years)and (half-life = 4.5 billion years).At a time 1.9 billion years ago,what was the fraction of In uranium?

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

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

Relativity

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An oxygen-15 nucleus, O,decays to another atomic nucleus by emitting a β⁺ ray.What is the other atomic nucleus?

Uranium-238 decays into thorium-234 plus an alpha particle.The known masses are He: 4.002603 u Th: 234.043583 u U: 238.050786 u How much energy is released in this process? (1 u = 931.5 MeV/c²)

Consider the nuclear reaction N + He → O + H.The known atomic masses are N: 14.003074 u He: 4.002603 u H: 1.007825 u O: 16.999131 u What is the Q-value (or reaction energy)of this reaction? (1 u = 931.5 MeV/c²)

The diameter of an atom is 1.4 × 10^-10 m and the diameter of its nucleus is 1.0 × 10^-14 m.What fraction of the atom's volume is occupied by its nucleus?

When a β^- particle is emitted from an unstable nucleus,the atomic number of the nucleus

A β^- decay occurs in an unstable nucleus when

In the fission reaction ²³⁵U + ¹n → ¹⁴¹Ba + ⁹²Kr + x ¹n,what is the number x of neutrons produced?