Why are some radioactive sources stored in boxes made from lead?
Lead absorbs emissions from the radioactive sources.
Lead decreases the half-life of radioactive sources.
Lead increases the half-life of radioactive sources.
Lead repels all radioactive emissions.
A
Which statement gives two safety precautions to take when a person is working with ionising radiation?
decrease exposure time and decrease distance between the person and the source
decrease exposure time and increase distance between the person and the source
increase exposure time and decrease distance between the person and the source
increase exposure time and increase distance between the person and the source
B
Several scientists are working in a laboratory. The scientists are experimenting with sources which emit ionising radiation. Each scientist is given a list of safety rules.
Three of the rules are shown.
1 Keep at least 2 m away from other people.
2 Do not stay longer than 4 hours per day in the laboratory.
3 Stay behind the lead-lined screen.
Which safety rules are for protection against the effects of ionising radiation?
1, 2 and 3
1 and 2 only
1 and 3 only
2 and 3 only
D