[positiveion]

I couldn't figure out how to answer this question:

A student wants to measure the half life of a radioactive isotope. He is told the isotope has a half life of between 10 and 20 minutes. Illustrating your answers appropriate, describe:

A). the measurements that he should take
B). how he should use the measurements to arrive at an estimate of the half life for the isotope.

I understand that to measure the half life of a radioactive material you measure the activity of the sample at regular times.

What I do not understand is the significance of the half life being between 10 and 20 minutes.

I also don't know how to do question b.

[Borek]

What I do not understand is the significance of the half life being between 10 and 20 minutes.

Most likely it is to help you decide how often you should take your activity measurements.

How does activity of the radioactive element change with time?