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Home / Doubts and Solutions/JEE/Physics

half life of a radioactive substance is 4 hours. After 20 hours, what is the fractional value of the substance left undecayed?

Asked by prashansh.kum100 23rd October 2018, 10:50 PM
Answered by Expert
Answer:
Half life = 4 hours
Number of half life in 20 hours = 20/4 = 5
fraction of undecayed radioactive material = 1/25 = 1/32
Answered by Expert 24th October 2018, 12:33 AM
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