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

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 time the permissible safe level. The minimum time after which it would be possible to work safely with this source is:
Answer» 6 hrs 12 hrs 24 hrs 128hrs Solution :For permissible safe level, the rate of DISINTEGRATION or activity of source should reduce to `1/(64)` times. `A/A_(0)=(1/2)^(t/T)=(1)/(64)=(1/2)^(6)` `t/T=6, t=6T=6 XX 2` =12hrs.

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

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