With no radioactive source present, a radiation detector is set to zero and switched on for 5 minutes. After this time, the counter displays:
1 2 5 \boxed{1}\;\boxed{2}\;\boxed{5} 125What radiation is the apparatus detecting?
Calculate the average count rate of this radiation in counts/min\text{counts/min}counts/min.
A source known to be highly radioactive is placed at a point 30 cm from the radiation detector. The counter is reset to zero and the count is taken again for 5 minutes. The counter now displays:
1 2 2 \boxed{1}\;\boxed{2}\;\boxed{2} 122State what type of radiation is being emitted by the source.
The source is moved to a position 3 cm from the detector. The counter is reset to zero and restarted. The counter reading after counting for 5 minutes is:
9 7 5 \boxed{9}\;\boxed{7}\;\boxed{5} 975Estimate the average count rate due to the radioactive source alone.
44 exam-style questions on CIE IGCSE Physics 5.2.1 Background radiation and measuring count rate. Each one has a worked solution and a mark scheme showing where the marks go.