Physics · 2019
JEE Main · 10 January 2019, Shift 1 · Q26
Using a nuclear counter the count rate of emitted particles from a radioactive source is measured. At t =0 it was 1600 counts per second and t =8…
Using a nuclear counter the count rate of emitted particles from a radioactive source is measured. At $\displaystyle \mathrm{t}=0$ it was $\displaystyle 1600$ counts per second and $\displaystyle \mathrm{t}=8$ seconds it was $\displaystyle 100$ counts per second. The count rate observed, as counts per second, at $\displaystyle \mathrm{t}=6$ seconds is close to :
Official answer
(2)
$\displaystyle 200$
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JEE Main 2019 Physics question, with the answer from NTA’s final answer key. Where our answers come from.