Question 1

Atoms of an element that have different atomic masses are called

Accepted Answer

A) ions 
B) isobars 
C) isotopes 
D) metastable 
E) dielectrics 
A) ions 
B) isobars 
C) isotopes 
D) metastable 
E) dielectrics B

Question 2

When a gamma ray passes through a material,

Accepted Answer

A) the gamma ray can cause photoelectric effect. 
B) the gamma ray can cause Compton scattering. 
C) the gamma ray can cause pair production. 
D) the gamma ray can pass right through the material unchanged. 
E) All the above processes can take place. 
A) the gamma ray can cause photoelectric effect. 
B) the gamma ray can cause Compton scattering. 
C) the gamma ray can cause pair production. 
D) the gamma ray can pass right through the material unchanged. 
E) All the above processes can take place. E

Question 3

Nuclear fusion takes place when

Accepted Answer

A) a large nucleus splits into two fragments with the release of a few neutrons. 
B) an $\alpha$ particle is ejected from the nucleus. 
C) a positive $\beta$ particle is ejected from the nucleus. 
D) small nuclei combine to form a larger one. 
E) heavy hydrogen is accelerated. 
A) a large nucleus splits into two fragments with the release of a few neutrons. 
B) an $\alpha$ particle is ejected from the nucleus. 
C) a positive $\beta$ particle is ejected from the nucleus. 
D) small nuclei combine to form a larger one. 
E) heavy hydrogen is accelerated. D

Question 4

Use the following atomic masses.  
-The neutrino was introduced as a part of the theory of beta decay because

Accepted Answer

A) the emitted beta particles are monoenergetic. 
B) Mparent daughter + Mbeta. 
C) there was an apparent violation of the conservation of energy,angular momentum,and linear momentum. 
D) the disintegration energy is less than zero (Q < 0). 
E) the conservation of charge and the conservation of nucleons are violated without the neutrino. 
A) the emitted beta particles are monoenergetic. 
B) Mparent daughter + Mbeta. 
C) there was an apparent violation of the conservation of energy,angular momentum,and linear momentum. 
D) the disintegration energy is less than zero (Q < 0). 
E) the conservation of charge and the conservation of nucleons are violated without the neutrino.

Question 5

The volume of a nucleus is directly proportional to the number of _______ it contains.

Accepted Answer

A) electrons 
B) protons 
C) neutrons 
D) isotopes 
E) nucleons 
A) electrons 
B) protons 
C) neutrons 
D) isotopes 
E) nucleons

Question 6

In gamma-decay a nucleus in an excited state decays to a lower energy state by the emission of a high energy photon called a gamma-ray.

Accepted Answer

A) Gamma-decay is always slow (greater than a ns). 
B) Gamma-decay is always fast (less than a ns). 
C) Gamma-decay is usually fast but can in special cases be slow. 
D) Gamma-decay is always accompanied by the emission of a neutrino. 
E) Gamma-decay is always accompanied by the emission of a $\beta$-particle. 
A) Gamma-decay is always slow (greater than a ns). 
B) Gamma-decay is always fast (less than a ns). 
C) Gamma-decay is usually fast but can in special cases be slow. 
D) Gamma-decay is always accompanied by the emission of a neutrino. 
E) Gamma-decay is always accompanied by the emission of a $\beta$-particle.

Question 7

Which of the following common isotopes has the highest binding energy per nucleon,4He,12C,16O,or 24Mg?

Accepted Answer

A) 4He 
B) 12C 
C) 16O 
D) 24Mg 
E) They are all the same. 
A) 4He 
B) 12C 
C) 16O 
D) 24Mg 
E) They are all the same.

Question 8

Cesium-137 has a half-life of 31.0 y.The time required for the cesium-137 now present to decrease to 1/30 its present value is

Accepted Answer

A) 930 y 
B) 30 y 
C) 465 y 
D) 152 y 
E) 1.6 y 
A) 930 y 
B) 30 y 
C) 465 y 
D) 152 y 
E) 1.6 y

Question 9

A radioactive sample is detected to produce 2500 decays per minute at 6:00 p.m.and 150 decays per minute at 11:00 p.m.the same day.What is the half-life of the sample?

Accepted Answer

A) 2.81 hrs 
B) 0.56 hrs 
C) 1.23 hrs 
D) 1.77 hrs 
E) 0.89 hrs 
A) 2.81 hrs 
B) 0.56 hrs 
C) 1.23 hrs 
D) 1.77 hrs 
E) 0.89 hrs

Question 10

Oxygen-15 is a $\beta$+ emitter that is often used in PET scans.It has a half-life of 122 seconds.Calculate how long it takes for the patient's initial activity to be reduced by a factor of 100.

Accepted Answer

A) 203 mins 
B) 1.22 $\times$ 104 mins 
C) 13.5 mins 
D) 8.13 mins 
E) None of these is correct. 
A) 203 mins 
B) 1.22 $\times$ 104 mins 
C) 13.5 mins 
D) 8.13 mins 
E) None of these is correct.

Question 11

A radioactive substance in the laboratory has a half-life of 8 h.At noon today,a Geiger counter reads 480 counts/min above background.At noon tomorrow,the counter should read about

Accepted Answer

A) 480 counts/min 
B) 240 counts/min 
C) 120 counts/min 
D) 60 counts/min 
E) 30 counts/min 
A) 480 counts/min 
B) 240 counts/min 
C) 120 counts/min 
D) 60 counts/min 
E) 30 counts/min

Question 12

A sample of   (which decays by $\beta$-emission)has an activity of 10.0 mCi.After 6.06 d it has an activity of 7.5 mCi.The half-life of 32P is approximately

Accepted Answer

A) 3.03 d 
B) 7.30 d 
C) 12.1 d 
D) 14.6 d 
E) 24.2 d 
A) 3.03 d 
B) 7.30 d 
C) 12.1 d 
D) 14.6 d 
E) 24.2 d

Question 13

The half-life of a radioactive substance is 5 min.Which of the following statements is true of the decay of this substance?

Accepted Answer

A) After 10 min,one-fourth of the original substance remains. 
B) The amount of the substance remaining after a given time is proportional to the number of minutes. 
C) The amount of the substance remaining after a given time is inversely proportional to the number of minutes. 
D) After 10 min,none of the original substance remains unchanged. 
E) None of these is correct. 
A) After 10 min,one-fourth of the original substance remains. 
B) The amount of the substance remaining after a given time is proportional to the number of minutes. 
C) The amount of the substance remaining after a given time is inversely proportional to the number of minutes. 
D) After 10 min,none of the original substance remains unchanged. 
E) None of these is correct.

Question 14

When an alpha particle (4He)with a kinetic energy of 6.54 MeV strikes a 27Al nucleus,a 30P nucleus is created and a neutron is ejected.Assume that the 30P nucleus has no final kinetic energy.Given the following masses for the various particles,what is the kinetic energy of the ejected neutron?

Accepted Answer

A) 3.71 MeV 
B) 2.83 MeV 
C) 6.54 MeV 
D) 9.37 MeV 
E) 0.45 MeV 
A) 3.71 MeV 
B) 2.83 MeV 
C) 6.54 MeV 
D) 9.37 MeV 
E) 0.45 MeV

Question 15

The superscript before the symbol for an element represents the number of

Accepted Answer

A) protons. 
B) neutrons. 
C) protons plus neutrons. 
D) protons minus neutrons. 
E) neutrons minus protons. 
A) protons. 
B) neutrons. 
C) protons plus neutrons. 
D) protons minus neutrons. 
E) neutrons minus protons.

Question 16

Neutrons produced in the fission of uranium are rapidly moving projectiles and must be slowed before they can produce more fission.If the neutrons collide elastically,hydrogen is effective in slowing them down because

Accepted Answer

A) hydrogen atoms repel neutrons. 
B) a hydrogen atom is much more massive than a neutron. 
C) a hydrogen atom and a neutron have about the same mass. 
D) a neutron is much more massive than a hydrogen atom. 
E) hydrogen atoms attract neutrons. 
A) hydrogen atoms repel neutrons. 
B) a hydrogen atom is much more massive than a neutron. 
C) a hydrogen atom and a neutron have about the same mass. 
D) a neutron is much more massive than a hydrogen atom. 
E) hydrogen atoms attract neutrons.

Question 17

A $\beta$ particle is an energetic

Accepted Answer

A) photon emitted by a nucleus. 
B) electron or positron. 
C) proton emitted by a nucleus. 
D) neutron emitted by a nucleus. 
E) None of these is correct. 
A) photon emitted by a nucleus. 
B) electron or positron. 
C) proton emitted by a nucleus. 
D) neutron emitted by a nucleus. 
E) None of these is correct.

Question 18

How much energy (in MeV)is released in the beta decay of a free neutron? Assume mass(proton)= 938.272 MeV/c2,mass(neutron)= 939.566 MeV/c2,mass(electron)= 0.511 MeV/c2,and mass(neutrino)= 0.000 MeV/c2.

Accepted Answer

A) 1.294 MeV 
B) 0.783 MeV 
C) 0.272 MeV 
D) 1.805 MeV 
E) Energy is not released in this decay. 
A) 1.294 MeV 
B) 0.783 MeV 
C) 0.272 MeV 
D) 1.805 MeV 
E) Energy is not released in this decay.

Question 19

The alpha particles from a naturally radioactive decay have a kinetic energy of 4.25 MeV.How close does an alpha particle come within a gold nucleus if the particle is heading directly towards the nucleus? Give your answer in terms of number of radii of the gold atom,r = 7.0 fm.

Accepted Answer

A) 2 
B) 8 
C) 12 
D) 15 
E) 19 
A) 2 
B) 8 
C) 12 
D) 15 
E) 19

Question 20

The radius of the 63Cu nucleus is approximately

Accepted Answer

A) 0.382 fm 
B) 5.97 fm 
C) 12.1 fm 
D) 24.2 fm 
E) 100 fm 
A) 0.382 fm 
B) 5.97 fm 
C) 12.1 fm 
D) 24.2 fm 
E) 100 fm

Exam 40: Nuclear Physics

Atoms of an element that have different atomic masses are called

When a gamma ray passes through a material,

Nuclear fusion takes place when

Use the following atomic masses. -The neutrino was introduced as a part of the theory of beta decay because

The volume of a nucleus is directly proportional to the number of _______ it contains.

In gamma-decay a nucleus in an excited state decays to a lower energy state by the emission of a high energy photon called a gamma-ray.

Which of the following common isotopes has the highest binding energy per nucleon,4He,12C,16O,or 24Mg?

Cesium-137 has a half-life of 31.0 y.The time required for the cesium-137 now present to decrease to 1/30 its present value is

A radioactive sample is detected to produce 2500 decays per minute at 6:00 p.m.and 150 decays per minute at 11:00 p.m.the same day.What is the half-life of the sample?

Oxygen-15 is a β\betaβ + emitter that is often used in PET scans.It has a half-life of 122 seconds.Calculate how long it takes for the patient's initial activity to be reduced by a factor of 100.

A radioactive substance in the laboratory has a half-life of 8 h.At noon today,a Geiger counter reads 480 counts/min above background.At noon tomorrow,the counter should read about

A sample of (which decays by β\betaβ -emission)has an activity of 10.0 mCi.After 6.06 d it has an activity of 7.5 mCi.The half-life of 32P is approximately

The half-life of a radioactive substance is 5 min.Which of the following statements is true of the decay of this substance?

When an alpha particle (4He)with a kinetic energy of 6.54 MeV strikes a 27Al nucleus,a 30P nucleus is created and a neutron is ejected.Assume that the 30P nucleus has no final kinetic energy.Given the following masses for the various particles,what is the kinetic energy of the ejected neutron?

The superscript before the symbol for an element represents the number of

Neutrons produced in the fission of uranium are rapidly moving projectiles and must be slowed before they can produce more fission.If the neutrons collide elastically,hydrogen is effective in slowing them down because

A β\betaβ particle is an energetic

How much energy (in MeV)is released in the beta decay of a free neutron? Assume mass(proton)= 938.272 MeV/c2,mass(neutron)= 939.566 MeV/c2,mass(electron)= 0.511 MeV/c2,and mass(neutrino)= 0.000 MeV/c2.

The alpha particles from a naturally radioactive decay have a kinetic energy of 4.25 MeV.How close does an alpha particle come within a gold nucleus if the particle is heading directly towards the nucleus? Give your answer in terms of number of radii of the gold atom,r = 7.0 fm.

The radius of the 63Cu nucleus is approximately

Systems of Measurement

Motion in One Dimension

Motion in Two and Three Dimensions

Newtons Laws

Applications of Newtons Laws

Work and Energy

Conservation of Energy

Systems of Particles and Conservation of Linear Momentum

Rotation

Conservation of Angular Momentum

Gravity

Static Equilibrium and Elasticity

Fluids

Oscillations

Wave Motion

Superposition and Standing Waves

Temperature and the Kinetic Theory of Gases

Heat and the First Law of Thermodynamics

The Second Law of Thermodynamics

Thermal Properties and Processes

The Electric Field I: Discrete Charge Distributions

The Electric Field Ii: Continuous Charge Distributions

Electric Potential

Capacitance

Electric Current and Direct-Current Circuits

The Magnetic Field

Sources of the Magnetic Field

Magnetic Induction

Alternating-Current Circuits

Maxwells Equations and Electromagnetic Waves

Properties of Light

Optical Images

Interference and Diffraction

Wave Particle Duality and Quantum Physics

Applications of the Schrodinger Equation

Atoms

Molecules

Solids and the Theory of Conduction

Relativity

Elementary Particles and the Beginning of the Universe

Filters

Which of the following common isotopes has the highest binding energy per nucleon,⁴He,¹²C,¹⁶O,or ²⁴Mg?

Oxygen-15 is a $\beta$ + emitter that is often used in PET scans.It has a half-life of 122 seconds.Calculate how long it takes for the patient's initial activity to be reduced by a factor of 100.

A $\beta$ particle is an energetic

How much energy (in MeV)is released in the beta decay of a free neutron? Assume mass(proton)= 938.272 MeV/c²,mass(neutron)= 939.566 MeV/c²,mass(electron)= 0.511 MeV/c²,and mass(neutrino)= 0.000 MeV/c².

The radius of the ⁶³Cu nucleus is approximately