Search any question & find its solution
Question:
Answered & Verified by Expert
The half-life of ${ }^{215} \mathrm{At}$ is $100 \mu \mathrm{s}$. The time taken for the radioactivity of a sample of ${ }^{215}$ At to decay to $1 / 16^{\text {th }}$ of its initial value is
Options:
Solution:
2110 Upvotes
Verified Answer
The correct answer is:
$400 \mu \mathrm{s}$
After $n$ half lives $N=N_0\left(\frac{1}{2}\right)^n$ $\therefore{ }^{215}$ At decays to $\frac{1}{16}^{\text {th }}$ in 4 half-lives i.e., after $400 \mu \mathrm{s}$.
Looking for more such questions to practice?
Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.