nuclear physics

is reciprocal to decay constant.

• Mean life

• half-life

• both a & b

• none of the above

A radioactive source emits radiation that can pass through a sheet of paper but not through thick aluminium. What does this show about the radiation?

• It is alpha-particles.

• It is beta-particles.

• It is gamma-rays.

• It is a mixture of alpha-particles and gamma-rays

Which line in the table describes the nature of an alpha-particle and a gamma-ray?

• A

• B

• C

• D

A radioactive nucleus R decays with the emission of a β-particle as shown:

Which equation is correct?

• x = p

• y = q

• p = x – 1

• q = y – 1

A narrow beam of alpha-particles is fired at a thin piece of gold foil.
Which is the final direction of the largest number of alpha-particles?

• A

• B

• C

• D

What is the half-life of this radioactive substance?

• 5700 years

• 11400 years

• 17100 years

• 22800 years

A student investigates a radioactive source that emits only alpha-particles. Without any source

nearby, the detector shows a low reading. The source and thick cardboard are placed near the detector, as shown:

What is the reading on the detector now, and why?

• A

• B

• C

• D

A proton consists of ...

• 2 up quarks and 1 down quark

• 1 up quark and 2 down quarks

• 1 up quark and 1 down quark

• 2 up quarks and 2 down quarks

• A: positron, B: electron neutrino

• A: electron, B: electron antineutrino

• A: alpha particle, B: proton

• A: alpha particle, B: neutron

This is an example of...

• Fission  reaction

• Fusion reaction

• Decomposition reaction

• Decay