The decay constant of a radioactive element is 1.5 × 10-9 per second. Its mean life in seconds will be:

Question

The decay constant of a radioactive element is 1.5 × 10-9 per second. Its mean life in seconds will be: (A) 1.5 × 109 (B) 4.62 × 108 (C) 6.67 × 108 (D) 10.35 × 108

Tardigrade Admin · Accepted Answer

Mean life =(1/λ) =(1/1.5 × 10-9) =6.67 × 108 sec

Q. The decay constant of a radioactive element is $1.5 \times 1 0^{- 9}$ per second. Its mean life in seconds will be:

$1.5 \times 1 0^{9}$

$4.62 \times 1 0^{8}$

$6.67 \times 1 0^{8}$

$10.35 \times 1 0^{8}$

Mean life $= \frac{1}{λ}$
$= \frac{1}{1.5 \times 1 0 ^{- 9}}$
$= 6.67 \times 1 0^{8} sec$

Q. The decay constant of a radioactive element is 1.5×10−9 per second. Its mean life in seconds will be:

1.5×109

4.62×108

6.67×108

10.35×108