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Physics · PYQ NEET UG 2018
हिन्दीFor a radioactive material, half-life is 10 minutes. If initially there are 600 number of nuclei, the time taken (in minutes) for the disintegration of 450 nuclei is
Correct answer · Option 1
20
Explanation
Remaining nuclei \( N = 600 - 450 = 150 \). Since \( N = N_0 (\frac{1}{2})^{t/T_{1/2}} \), so \( 150 = 600 (\frac{1}{2})^{t/10} \implies (\frac{1}{2})^2 = (\frac{1}{2})^{t/10} \implies t = 20\text{ minutes} \).
