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A radioactive sample undergoes decay as ...

A radioactive sample undergoes decay as per the following gragp. At time` t=0`, the number of undecayed nuclei is `N_(0)`. Calculate the number of nuclei left after `1 h`.
.

A

`(N_(0))/(e^(8))`

B

`(N_(0))/(e^(10))`

C

`(N_(0))/(n^(12))`

D

`(N_(0))/(e^(14))`

Text Solution

Verified by Experts

The correct Answer is:
C
`t=0,N=N_(0)`
t=6.93 min, `N=(N_(0))/(4)`
`N_(0)/4` is the sample left after two half lives.
`2T_(1//2)=6.93` or `T_(1//2)=(6.93)/(2)` min
`lamda=(0.693)/(T_(1//2))=0.2"minute"^(-1)`
at time t=1h=60 minute
`N=N_(0)e^(-lamdat)=N_(0)e^(-0.2xx60)=(N_(0))/(e^(12))`
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