# A freshly prepared radioactive material has an half life 2 years.It emits radiaion which is 64 times the permissibile safe level dose.The min. time after which it would be possible to work safely with the source is_____________

17 Points
15 years ago

Let the permissible radiation level be K. Current emission is 64K

In 2 years, it will emit 32K

In 4 years, it will emit 16K

in 6 years, it emits 8K

and so on

In 12 years, the sample will emit radiation at level K, which is suitable for work

Ramesh V
70 Points
15 years ago

half-life period = 2 yrs

since it emits 64 times the permissible level

time after which it works safrly is : 2n=64

n=6 half lifes

so, after 12 years , its safe to work with radioactive material

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Naga Ramesh
IIT Kgp - 2005 batch

4 years ago
Dear student,

half-life period = 2 yrs
since it emits 64 times the permissible level
time after which it works safrly is : 2n=64
n=6 half lifes
so, after 12 years , its safe to work with radioactive material.

Hope it helps.
Thanks and regards,
Kushagra