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Grade 12 Radioactivity & Half-Life Worksheet with Answers
Grade 12 (US) · Year 13 (UK) · Class 12 (India) · Physics
Unit 4: Modern PhysicsNuclear DecayNGSS HS-PS1-8
Calculating how much of a radioactive sample remains, and dating with half-lives. This free high school worksheet has 12 questions and a full answer key. Print it or save it as a PDF — every answer is checked by code, not guessed.
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Practice Sheetaethelsystems.comRadioactivity & Half-Life
Grade 12 · Physics
Name
Class
Date
Learning goal: Nuclear Decay · NGSS HS-PS1-8
Directions: Read each question carefully and write your answer on the line. Use the diagram to help you.
A 320 g sample has a half-life of 5 days. How much remains after 5 days?
Answer: 160 g
RememberHalf-life
- 1
A sample with a half-life of 12 days drops from 1000 g to 500 g. How much time has passed?
- 2
A sample with a half-life of 10 days drops from 800 g to 400 g. How much time has passed?
- 3
A 200 g sample has a half-life of 5730 years. How much remains after 17190 years?
- 4
A sample with a half-life of 12 days drops from 200 g to 25 g. How much time has passed?
- 5
A sample with a half-life of 5 days drops from 1000 g to 125 g. How much time has passed?
- 6
A sample with a half-life of 30 days drops from 800 g to 400 g. How much time has passed?
- 7
A sample with a half-life of 12 days drops from 400 g to 100 g. How much time has passed?
- 8
A sample with a half-life of 30 days drops from 320 g to 160 g. How much time has passed?
- 9
An 800 g sample has a half-life of 8 days. How much remains after 24 days?
- 10
An 80 g sample has a half-life of 5730 years. How much remains after 5730 years?
- 11
A 1000 g sample has a half-life of 20 days. How much remains after 60 days?
- 12
A sample with a half-life of 30 days drops from 320 g to 40 g. How much time has passed?
★ Challenge corner for fast finishers
Does a kilogram of feathers weigh more than a kilogram of iron?
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Teacher's comments
Free printable worksheets with answer keys · aethelsystems.com/worksheets/physics/12/half_life
Answer key — Radioactivity & Half-Life (Grade 12)
- 1.12 days
- 2.10 days
- 3.25 g
- 4.36 days
- 5.15 days
- 6.30 days
- 7.24 days
- 8.30 days
- 9.100 g
- 10.40 g
- 11.125 g
- 12.90 days
- ★no — they weigh the same
Answer key (click to show)
- 1.12 days
- 2.10 days
- 3.25 g
- 4.36 days
- 5.15 days
- 6.30 days
- 7.24 days
- 8.30 days
- 9.100 g
- 10.40 g
- 11.125 g
- 12.90 days
- ★no — they weigh the same (challenge corner)
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