Activity and half-life (HT)

This lesson explores the pattern behind the randomness of radioactive decay, how the half-life of an isotope can be determined and how the proportion of nuclei lost can be determined.

Video

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Worksheet

These slides will take you through some tasks for the lesson. If you need to re-play the video, click the ‘Resume Video’ icon. If you are asked to add answers to the slides, first download or print out the worksheet. Once you have finished all the tasks, click ‘Next’ below.

Quiz:

Activity and Half-life (HT)

Complete the quiz to see how much you have remembered.

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Q1.What is the best definition of 'activity'?

1/6

Q2.What is the best definition of 'half life'?

2/6

Q3.What is the best definition of 'count rate'?

3/6

Q4.What is activity measured in?

4/6

Q5.If a radioactive sample contained 1600 billion nuclei and its half life was 57 years, after how many years would there be 400 billion nuclei remaining?

5/6

Q6.A radioactive isotope has a half-life of 20 hours. How long will it take for 3/4 of the source to decay?

6/6

Quiz:

Activity and Half-life (HT)

Complete the quiz to see how much you have remembered.

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Q1.What is the best definition of 'activity'?

1/6

Q2.What is the best definition of 'half life'?

2/6

Q3.What is the best definition of 'count rate'?

3/6

Q4.What is activity measured in?

4/6

Q5.If a radioactive sample contained 1600 billion nuclei and its half life was 57 years, after how many years would there be 400 billion nuclei remaining?

5/6

Q6.A radioactive isotope has a half-life of 20 hours. How long will it take for 3/4 of the source to decay?

6/6

Lesson summary: Activity and half-life (HT)

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