A student is investigating how the radiation from a radioactive source changes with time. The table shows the results from the detector.
The experiment is repeated by other students, who also measure the count rate every two minutes. The half-life of the source is known to be exactly two minutes. Why is the measured count rate always higher than half the previous value?
Radioactive emissions occur randomly with time.
The detector used is very close to the source.
There is background radiation present.
The radioactive source is decaying
