Half-Life (OCR GCSE Physics A, Combined (Gateway Science Suite)): Quizzes
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Practise the questions
12 questions from this quiz
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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 nuclei to decay
A sample of atoms falls to atoms in minutes. What is the half-life?
A sample of atoms falls to atoms in minutes. What is the half-life?
5 minutes
What characteristic describes a substance with a short half-life?
What characteristic describes a substance with a short half-life?
Very radioactive, quickly dies down
What is the half-life of Americium?
What is the half-life of Americium?
432 years
Why is Americium suitable for smoke alarms?
Why is Americium suitable for smoke alarms?
Won't need replenishment, weak activity
Which device measures radioactivity count rate?
Which device measures radioactivity count rate?
Geiger-Muller tube and counter
What does an activity of Bq represent?
What does an activity of Bq represent?
1 decay per second
How does the activity of a radioactive source change over time?
How does the activity of a radioactive source change over time?
Decreases but never reaches zero
Initial activity is Bq. What percentage remains after half-lives?
Initial activity is Bq. What percentage remains after half-lives?
25%
Half-life is days, initial count rate counts/s. Count rate after days?
Half-life is days, initial count rate counts/s. Count rate after days?
25 counts/s
What is true about predicting radioactive decay?
What is true about predicting radioactive decay?
Decay is completely random process
What does count rate measure?
What does count rate measure?
Radiation counts per second