(a(i))[1]
State the pair of nuclei that contain the same number of protons.
(a(ii))[1]
State the pair of nuclei that have the same number of neutrons.
(a(iii))[1]
State the pair of nuclei that contain the same number of nucleons.
(b(i))[1]
State the meaning of ‘background radiation’.
(b(ii))[1]
The measured count rate is 420 counts per minute and background radiation must be allowed for. Calculate the corrected count rate from the source.
(b(iii))[2]
The radioactive source has a half-life of 45 minutes. Determine the counter reading after 90 minutes.
(b(iv))[1]
Suggest why the answer to (iii) is only an estimate.
(c)[2]
Fig. 7.1 presents different applications of three kinds of radiation. Draw a line on Fig. 7.1 from each use of radiation to the type of radiation used. One line has already been drawn for you.