MCQs – Nuclear energy (set 2)

• β⁻ decay

• fusion

• β⁺ decay

• fission

Fast neutrons can easily be slowed down by

• the use of lead shielding.

• passing them through water.

• elastic collisions with heavy nuclei.

• applying a strong electric field.

What is the approximate mass of a nucleus of uranium?

• 10^-15 kg

• 10^-20 kg

• 10^-25 kg

• 10^-30 kg

Which of the following statements about nuclear fission is correct?

• A uranium-235 nucleus can only undergo fission after absorbing a proton.

• Kinetic energy is conserved during fission.

• Linear momentum is not conserved during fission.

• The fission fragments have a total mass less than that of the nucleus just before fission.

• 14 MeV

• 27 MeV

• 24 MeV

• 19 MeV

The fuel used in a nuclear fission reactor is uranium. Which of the following is required for fission to proceed?

• Neutrons must be removed from the reactor core.

• The uranium nuclei must absorb neutrons.

• The reactor core must be very hot.

• The uranium nuclei must absorb protons.

Data from the first page of the formula sheet can be used with the equation ΔE = c²Δm to calculate

• the amount of energy in a proton.

• the mass of coal that produces 6.0 MJ of energy when burnt.

• the energy produced when an electron and a positron annihilate.

• the energy produced when two protons collide.

A uranium-238, originally at rest, decays by emitting an α-particle that has a velocity v. The recoil velocity of the residual nucleus is

• an α-particle

• a β-particle

• a neutron

• a proton

Fission and fusion are both nuclear processes. Which of the following statements is correct for both processes?

• The total mass increases.

• Neutrons are released.

• No harmful radiation is produced.

• The binding energy per nucleon increases.