Question

A sample of a radioactive element has a mass of 10g at an instant t = 0. The oppropriate mass of this element in the element in the sample after two mean lives is

Solution

Correct option is

1.35 gm

t = 2    τ = 2 × 1.44 T = 2.88 T

            

             

                = 10 × .1358 = 1.358 gm.

SIMILAR QUESTIONS

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Q8

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Q9

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Q10

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