Radiations - MC

Which row describes alpha, beta and gamma radiations?

• A

• B

• C

• D

• E

Alpha radiation ionises an atom. Which statement describes what happens to the atom?

• The atom splits in half.

• The atom releases a neutron.

• The atom becomes positively charged.

• The atom gives out gamma radiation.

• The atom releases heat.

During ionisation an atom becomes a positive ion. Which of the following has been removed from the atom?

• An alpha particle

• An electron

• A gamma ray

• A neutron

• A proton

A sample of tissue is irradiated using a radioactive source. Which statements are correct?

• The equivalent dose received by the sample is reduced by shielding the sample with a
  lead screen.

• The equivalent dose received by the sample is increased as the distance from the
  source to the sample is increased.

• The equivalent dose received by the sample is increased by increasing the time of
  exposure of the sample to the radiation.

Which of the following statements about the activity of a radioactive source is/are correct?

• The activity decreases with time.

• The activity is measured in becquerels.

• The activity is the number of decays per second.

For a particular radioactive source, 240 atoms decay in 1 minute.
The activity of this source is

• 4 Bq

• 180 Bq

• 240 Bq

• 300 Bq

• 14 400 Bq

A radioactive sample emits 3000 alpha particles in 2 minutes.
The activity of the sample is:

• 25 Bq

• 1500 Bq

• 3000 Bq

• 6000 Bq

• 360 000 Bq

During radiation treatment, a patient’s liver absorbs 90 μJ of gamma radiation.
The mass of the liver is 2·0 kg.
The absorbed dose received by the liver is

• 45 μGy

• 88 μGy

• 90 μGy

• 92 μGy

• 180 μGy

A sample of tissue receives an absorbed dose of 16 µGy from alpha particles.
The radiation weighting factor for alpha particles is 20.
The equivalent dose received by the sample is

• 0·80 µSv

• 1.25 µSv

• 4 µSv

• 36 µSv

• 320 µSv

A worker in a nuclear power station is exposed to 3∙00 mGy of gamma radiation and
0∙500 mGy of fast neutrons.
The total equivalent dose received by the worker is

• 3.5 mSv

• 8.00 mSv

• 30.5 mSv

• 35.0 mSv

• 38.5 mSv