Question:
The half-life of a radioactive substance is $30$ minutes. The time (in minutes) taken between $40\%$ decay and $85\%$ decay of the same radioactive substance is
The half-life of a radioactive substance is $30$ minutes. The time (in minutes) taken between $40\%$ decay and $85\%$ decay of the same radioactive substance is
Updated On: Nov 6, 2024
- 15
- 30
- 45
- 60
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The Correct Option is D
Solution and Explanation
$N_1 = 0.6 \, N_0$
$N_2 = 0.15 \, N_0$
$\frac{N_2}{N_1} = (\frac{1}{2} )^2$ so two half life period has passed
So time taken $2t_{1/2} = 2 \times 30 = 60$ minutes
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Concepts Used:
Half-life
The amount of time taken for half of a particular sample to react is known as Half-life.
Half-Life Formula:
We can describe exponential decay by any of the three formulas
