Nuclear Fusion & Fission (AQA A Level Physics): Exam Questions

Boron-10 is a stable isotope of boron with a relative atomic mass of 10.01294 u. 

What is the binding energy per nucleon of a boron-10 nucleus? 

Use the following data:

• Atomic number of boron = 5

• Mass of a proton = 1.00728 u

• Mass of a neutron = 1.00867 u

• 1 u = 931.5 MeV

A stationary uranium-238 nucleus decays by alpha-emission, as shown in the equation below:  

                ${}_{92}{}^{238}U\to {}_{90}{}^{234}Th+{}_2{}^4\alpha$

This decay generates a total energy E. 

Which of the following statements is correct regarding the kinetic energy of the alpha particle ${}_2{}^4\alpha$?

Which statement about nuclear power is incorrect?

The graph below shows how the average binding energy per nucleon varies with nucleon number for stable nuclei.

Approximately how much energy is released when the nucleus ${}_{70}{}^{181}X$ forms?

Nitrogen-14 can be transformed into Oxygen-17 by bombardment with high energy alpha particles, as described in the nuclear reaction equation below: 

                ${}_7{}^{14}N+{}_2{}^{4}He\to {}_8{}^{17}O+{}_1{}^{1}H$

The total rest-mass of the reactants is 18.006 u and total rest mass of the products is 18.007 u. 

Which of the following statements about this reaction is correct?

In a nuclear fission reactor, the purpose of the moderator is to

A nuclear fusion reaction involving deuterium and tritium is described by the nuclear equation below: 

               ${}_1{}^{2}H+{}_1{}^{3}H\to {}_2{}^{4}He+{}_0{}^{1}n$ + energy

How many such fusion reactions would be required keep an average household, which uses approximately 2000 kWh of electric energy per month, running for a month? 

You may use the following data:

• Mass of  ${}_1{}^{2}H$ = 2.014102 u

• Mass of  ${}_1{}^{3}H$ = 3.016049 u

• Mass of  ${}_2{}^{4}He$ = 4.002602 u

• Mass of ${}_0{}^{1}n$ = 1.008665 u

A nuclear reaction is given below: 

            ${}_{92}{}^{235}\mathrm{U}+{}_0{}^1\mathrm{n}\to {}_{56}{}^{142}\mathrm{Ba}+{}_{36}{}^{91}\mathrm{Kr}+3{}_0{}^1\mathrm{n}$

You may use the following data:

• Mass of ${}_{92}{}^{235}\mathrm{U}$ = 235.0439 u

• Mass of  ${}_{56}{}^{142}\mathrm{Ba}$ = 141.9164 u

• Mass of ${}_{36}{}^{91}\mathrm{Kr}$ = 90.9234 u

How much energy is released in this reaction?

Sometimes, a gamma ray photon accompanies two alpha particles when lithium nuclides ${}_3{}^{7}Li$ are bombarded by high-speed protons. 

When this happens, the kinetic energy of the alpha particles after the reaction is measured to be about 16.5 MeV. 

What is the frequency of the gamma ray photon emitted? 

The following data may be used:

• Mass of  ${}_3{}^{7}Li$= 7.0160 u

• Mass of a proton = 1.0080 u

• Mass of an alpha particle = 4.0026

Burning one metric tonne (1000 kg) of coal can yield 3.30 × 10¹⁰ J of energy, while the fission of a single uranium-235 nucleus yields, on average, a much larger amount of energy. 

When a thermal neutron is absorbed by a uranium-235 nucleus, it produces fission products as well as three neutrons, as given by the equation below: 

             ${}_0{}^{1}n+{}_{92}{}^{235}U\to {}_{40}{}^{98}Zr+{}_{52}{}^{135}Te+3{}_0{}^{1}n$+ energy 

What is the mass of coal needed to give the same amount of energy as 1 kg of uranium-235? 

You may use the following data:

• Mass of ${}_0{}^{1}n$= 1.00866 u

• Mass of  ${}_{92}{}^{235}U$= 235.0439 u

• Total mass of  ${}_{40}{}^{98}Zr+{}_{52}{}^{135}Te$  = 232.8292 u

A nucleus ${}_Z{}^{A}X$ has a mass M. 

Which of the following expressions correctly represents the binding energy per nucleon of this nucleus in terms of the speed of light c, the mass of a proton $m_p$ and the mass of a neutron $m_n$?