At a given instant there are 25% of undecayed radio- active nuclei in a sample. After 10S, the number of undecayed nuclei reduces to 12.5%. The time in which the number of undecayed nuclei will further reduced to 6.25% of the reduced number is,

At a given instant there are 25% of undecayed radio- active nuclei in

1.	At a given instant there are 25% of undecayed radio- active nuclei in a sample. After 10S, the number of undecayed nuclei reduces to 12.5%. The time in which the number of undecayed nuclei will further reduced to 6.25% of the reduced number is,
Answer» 20 Sec 30 Sec 10 Sec 40 Sec ANSWER :C

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At a given instant there are 25% of undecayed radio- active nuclei in a sample. After 10S, the number of undecayed nuclei reduces to 12.5%. The time in which the number of undecayed nuclei will further reduced to 6.25% of the reduced number is,

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