A) 15 days
B) 60days
C) 30 days
D) 25 days
Correct Answer: C
Solution :
Here ratio of left mass to original \[=\frac{1}{10}={{\left( \frac{1}{2} \right)}^{4}}\] i.e. 16g of substance has reduced to 1g after 4 half-life. \[n=4\] But \[n=\frac{t}{{{T}_{1/2}}}\] \[\Rightarrow \] \[4=\frac{120}{{{T}_{1/2}}}\] \[\therefore \] half life of substance \[{{T}_{1/2}}=\frac{120}{4}=30\] days.You need to login to perform this action.
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