Half-life (Edexcel GCSE Physics Combined Science): Quizzes
📚Quizzes
Practise the questions
11 questions from this quiz
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Practise the questions
11 questions from this quiz
What is half-life?
What is half-life?
Time for half of unstable nuclei to decay
What does the activity of a radioactive substance measure?
What does the activity of a radioactive substance measure?
Decays per second
What does 1 Bq mean?
What does 1 Bq mean?
One decay per second
Why is radioactive decay described as a random process?
Why is radioactive decay described as a random process?
Can't predict when an atom will decay
What happens to unstable nuclei after one half-life passes?
What happens to unstable nuclei after one half-life passes?
Number reduced by half
Thorium-243 has 600 counts/s activity. What is activity after 25 days (1 half-life)?
Thorium-243 has 600 counts/s activity. What is activity after 25 days (1 half-life)?
300 counts per second
For Thorium-243, what is the activity after 50 days (2 half-lives)?
For Thorium-243, what is the activity after 50 days (2 half-lives)?
150 counts per second
A sample has a 30 min half-life. How many half-lives pass in 2 hours?
A sample has a 30 min half-life. How many half-lives pass in 2 hours?
4 half-lives
40,000 nuclei, 30 min half-life. How many nuclei remain after 2 hours?
40,000 nuclei, 30 min half-life. How many nuclei remain after 2 hours?
2,500 nuclei
80 nuclei decay to 40 nuclei in 2 days. What is the half-life?
80 nuclei decay to 40 nuclei in 2 days. What is the half-life?
2 days
What happens to activity after each half-life?
What happens to activity after each half-life?
Decreases by half