Physics · Nuclear Physics
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The ratio between mean life and half-life is:
- A
Log2
- B
1/log λ
- C
1/λ
- D
(Log2)-1
We have to remember formula
Mean life = 1/lambda
Half life = log2 / lambda
=log2 × 1/lambda
Replacing 1/lambda by mean life,
Half life = log2 × mean life…….(i)
Ratio required= mean life/ half life
From equation (i)
Mean life/half life = 1 / log2
= (log2)-¹
This option is incorrect.We have to remember formula
Mean life = 1/lambda
Half life = log2 / lambda
=log2 × 1/lambda
Replacing 1/lambda by mean life,
Half life = log2 × mean life…….(i)
Ratio required= mean life/ half life
From equation (i)
Mean life/half life = 1 / log2
= (log2)-¹
If in place of lambda there is 2 then it could be right option.
It's also wrong, it is the mean life not the given ratio.
right option as proved
We have to remember formula
Mean life = 1/lambda
Half life = log2 / lambda
=log2 × 1/lambda
Replacing 1/lambda by mean life,
Half life = log2 × mean life…….(i)
Ratio required= mean life/ half life
From equation (i)
Mean life/half life = 1 / log2
= (log2)-¹
Tagged under Physics · Nuclear Physics · 2005