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A freshly prepared radioactive source of...

A freshly prepared radioactive source of half-life 2 h emits radiation of intensity which is 64 times the permissible safe level. The minimum time after which it would be possible to work safely with this source is

A

`6 h`

B

`12 h`

C

`24 h`

D

`128 h`

Text Solution

Verified by Experts

The correct Answer is:
B
`64=2^(6)`
After `6` half lives activity will become `=(1)/(64)`
Hence required time `=6xx2h=12h`
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RESONANCE ENGLISH-NUCLEAR PHYSICS-Exercise-1 Part-2 Only one option correct type
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