Radioactivity Quiz

In which direction is the beam of β-particles deflected as they enter the magnetic field?

• into the page

• out of the page

• down the page

• up the page

Which type of radiation is suitable to use?

• α-particles only

• β-particles only

• either α-particles or β-particles

• γ-rays only

• A

• B

• C

• D

What is the half-life of the source?

• 10 min

• 20 min

• 40 min

• 60 min

In this decay, the nucleus changes by

• absorbing a neutron.

• absorbing a proton.

• emitting an α-particle.

• emitting a β-particle.

What will be the decay rate at 8 days?

• 0 decays/s

• 125 decays/s

• 250 decays/s

• 500 decays/s

What is the emitted particle?

• α-particle

• β-particle

• neutron

• proton

The reading on a detector placed near a radioactive material is 536 counts per second.

The background count rate is 44 counts per second.

The half-life of the radioactive material is 34 hours.

What is the reading on the detector after 68 hours?

• 44 counts per second

• 123 counts per second

• 134 counts per second

• 167 counts per second

How do the γ-rays pass between the two charged plates?

• The rays are deflected in a direction perpendicular to the page

• The rays are deflected towards the negative plate.

• The rays are deflected towards the positive plate.

• The rays will continue in the same direction.

A powder contains 400 mg of a radioactive isotope that emits α-particles.

The half-life of the isotope is 5 days.

What mass of this isotope remains after 10 days?

• 0 mg

• 40 mg

• 100 mg

• 200 mg