Question:
A freshly prepared radioactive source of half life 2 hours 30 minutes emits radiation which is 64 times the permissible safe level. The minimum time, after which it would be possible to work safely with source, will be _______ hours.
A freshly prepared radioactive source of half life 2 hours 30 minutes emits radiation which is 64 times the permissible safe level. The minimum time, after which it would be possible to work safely with source, will be _______ hours.
Updated On: Mar 19, 2025
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Correct Answer: 15
Solution and Explanation
Given here, T=150 minutes, A0=64x, where, x is the safe limit.
Using the radioactive decay law relation,
A=A0×2\(^{\frac{-t}{T}}\), where, t is the minimum time in hours after which it would be possible to work safely with source.
Putting the values, we have x=64x×2\(^{\frac{-t}{T}}\)
∴ t=6T=6×2.5=15 hours
Using the radioactive decay law relation,
A=A0×2\(^{\frac{-t}{T}}\), where, t is the minimum time in hours after which it would be possible to work safely with source.
Putting the values, we have x=64x×2\(^{\frac{-t}{T}}\)
∴ t=6T=6×2.5=15 hours
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Concepts Used:
Half-life
The amount of time taken for half of a particular sample to react is known as Half-life.
Half-Life Formula:
We can describe exponential decay by any of the three formulas
