. A freshly prepared radioactive source of half


life 2 hours emits radiation of intensity which is 32 times the permissible safe level.

The minimum time after which it would be possible to work safely with the source is

A: 6 hours

B: 10 hours

C: 24 hours

D: 128 hours

 

Best Answer

Explanation:-

A radioactive substance undergoes continuous disintegration. 

There are atoms which disintegrate in the beginning. 

There are atoms which disintegrate at the end. 

Half life of a radioactive substance is defined as the time during which half of the number of atoms present initially in the

sample of the element decay or the time during which number of atoms left undecayed in the sample are half the total number of atoms present initially in the sample.

Here, half-life of the radioactive substance, T = 2 hours.

Amount of radioactive substance left after time,

prepared radioactive

Final answer:-

Hence ,the correct option is (B) i.e. 10 hours.

 

Talk to Our counsellor