In the radioactive decay of an element it is found that the count rate reduces from 1024 to 128 in 3 minutes. Its half life will be

Question

In the radioactive decay of an element it is found that the count rate reduces from 1024 to 128 in 3 minutes. Its half life will be (A) 1 minute (B) 2 minute (C) 3 minute (D) 5 minute

Tardigrade Admin · Accepted Answer

(R/R0)=(128/1024) (R/R0)=(1/8) or (R/R0)=((1/2))3 ∴ n=3 3 half lives in 3 minutes, 1 half life in 1 minute

Q. In the radioactive decay of an element it is found that the count rate reduces from $1024$ to $128$ in $3$ minutes. Its half life will be

1 minute

2 minute

3 minute

5 minute

$\frac{R}{R _{0}} = \frac{128}{1024}$
$\frac{R}{R _{0}} = \frac{1}{8}$
or $\frac{R}{R _{0}} = (\frac{1}{2})^{3}$
$∴ n = 3$
$3$ half lives in $3$ minutes, $1$ half life in $1$ minute

Q. In the radioactive decay of an element it is found that the count rate reduces from 1024 to 128 in 3 minutes. Its half life will be