Half-life (AQA GCSE Physics): Quizzes
📚Quizzes
Practise the questions
12 questions from this quiz
ShowHide
Practise the questions
12 questions from this quiz
What is the definition of half-life?
What is the definition of half-life?
Time for half the unstable atoms to decay
What is the unit used to measure the activity of a radioactive source?
What is the unit used to measure the activity of a radioactive source?
Becquerels (Bq)
What does a becquerel tell us?
What does a becquerel tell us?
How many atoms decay each second
What can we predict about radioactive decay?
What can we predict about radioactive decay?
Overall pattern for large samples
What percentage of radioactive atoms remain after 1 half-life?
What percentage of radioactive atoms remain after 1 half-life?
50%
What percentage of radioactive atoms remain after 2 half-lives?
What percentage of radioactive atoms remain after 2 half-lives?
25%
What percentage of radioactive atoms remain after 3 half-lives?
What percentage of radioactive atoms remain after 3 half-lives?
12.5%
A source has activity 800 Bq and half-life 5 hours. What is the activity after 10 hours?
A source has activity 800 Bq and half-life 5 hours. What is the activity after 10 hours?
200 Bq
How does activity change with each half-life period?
How does activity change with each half-life period?
It halves each time
What shape is a half-life graph?
What shape is a half-life graph?
Curved, getting less steep over time
What is the name of the curve shown on a half-life graph?
What is the name of the curve shown on a half-life graph?
Exponential decay curve
To find half-life from a graph starting at 1000 Bq, where should you look?
To find half-life from a graph starting at 1000 Bq, where should you look?
Where it crosses 500 Bq