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90% of a radioactive sample is left unde...

`90%` of a radioactive sample is left undecayed after time `t` has elapesed. What percentage of the initial sample will decay in a total time `2 t` ?

A

0.2

B

0.19

C

0.4

D

0.38

Text Solution

Verified by Experts

The correct Answer is:
B
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MOTION-RADIOACTIVITY & NUCLEAR PHYSICS-Exercise -1
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  2. A radioactive sample at any instant has its disintegration rate 5000 d...

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  3. 90% of a radioactive sample is left undecayed after time t has elapese...

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  4. A radio active sample contains 10^(6) radioactive nucleus it s h...

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  5. 1 mg radium has 2.68 xx 10^(18) atoms. Its half-life is 1620 years. Ho...

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  6. If the activity of radioactive sample drops to 1//32 of its initi...

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  7. A freshly prepared radioactive source of half life period of 2 hour em...

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  8. A radioactive sample contains two elements P and Q . The mass ...

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  9. The radioactive sources A and B of half lives of 2hr and 4hr respectiv...

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  10. The half life of polonium is 140 days. In what time will 15 g of polon...

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  11. The half life of radium is 1600 years . In how much time will ...

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  12. Calculate the half life period of a radioactive substance if its activ...

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  13. When 64 gms of a radioactive element are carried from Jaipure t...

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  14. A radioactive element with mass 8 gm and haslf life 100 second ...

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  15. The activity of a radioactive elements (decay constant lambda) ...

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  16. A fraction f(1) of a radioactive sample decays in one mean lie and a f...

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  17. What percentage of the atoms in a sample will remain undecayed...

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  18. In a RA element the fraction of initiated amount remaining after...

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  19. The mean lives of a radioactive material for alpha and beta rad...

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  20. Activity of a radioactive substance is R(1) at time t(1) and R(2) ...

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