A freshly prepared radioactive source of half-life 2 hours emits radiations 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 [IIT 1988]

A freshly prepared radioactive source of half-life 2 hours emits radia

1.	A freshly prepared radioactive source of half-life 2 hours emits radiations 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 [IIT 1988]
A.	6 hours
B.	12 hours
C.	24 hours
D.	128 hours
Answer» C. 24 hours

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A freshly prepared radioactive source of half-life 2 hours emits radiations 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 [IIT 1988]

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