Quick questions on Radioactive decay explained: H2 Physics Modern Physics

5short Q&A pairs drawn directly from our worked dot-point answer. For full context and worked exam questions, read the parent dot-point page.

What is the exponential decay law?

Show answer

The number of undecayed nuclei follows:

What is half-life?

Show answer

The half-life

t_{1/2}

is the time for half the undecayed nuclei (and so half the activity) to decay. Setting

N = \tfrac{1}{2}N_0

in the decay law gives:

What is q1?

Show answer

State what is meant by the activity of a radioactive source and its unit. [2 marks]

What is q2?

Show answer

An isotope has a decay constant of

0.050\ \text{s}^{-1}

. Find its half-life. [2 marks]

What is q3?

Show answer

A source has an initial activity of

1.6 \times 10^5\ \text{Bq}

and a half-life of

2.0

hours. Find its activity after

6.0

hours. [2 marks]

Have a question we have not covered?

This dot-point answer is short enough that we have not extracted many short questions yet. Read the full dot-point answer or ask Mo, our study assistant, in the chat for follow ups.

All PhysicsQ&A pages