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In a freshly prepared radioactive sample...

In a freshly prepared radioactive sample the rate of radiation is 64 times greater than the safe limit. If its half -life be 2 h then using this sample experiments can be performed with safely after

A

6 h

B

12 h

C

24 h

D

128 h

Text Solution

Verified by Experts

The correct Answer is:
B
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CHHAYA PUBLICATION-ATOMIC NUCLEUS-EXERCISE
  1. An excited Ne^22 nucleus is disintegrated into an unknown nucleus and ...

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  2. The half-life of I^131 is 8d. If a sample of I^131 is taken at time t=...

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  3. In a freshly prepared radioactive sample the rate of radiation is 64 t...

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  4. The mean life of a radioactive element is 13 days. Initially a sample ...

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  5. The half-life of At^215 is 100 mus.The time taken for the radioactivit...

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  6. The half-life of a radioactive substance is 20 min. The approximate t...

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  7. The half-life of a radioactive isotope X is 50 years . It decays to an...

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  8. A nucleus .n^mX emits one alpha particle and two beta^- particles .The...

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  9. Two radioactive nuclei P and Q in a given sample decay into a stable n...

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  10. Of the following equations which one is the probable nuclear fusion re...

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  11. In the nuclear reaction .7^14N + X to .6^14C + .1^1H the X will be

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  12. Fast moving neutrons are retarded

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  13. In nuclear fusion,

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  14. 4.1H^1 to .2He^4 + 2e^(+)+ 26 MeV : this is an equation of

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  15. The power obtained in a reactor using U^235 disintegration is 1000 kW....

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  16. What is the relation between unified atomic mass unit (u) and electron...

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  17. The mass of a proton or a neutron is nearly 1.67xx10^(-24) g . What i...

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  18. What is the order of magnitude of the density of nuclear matter ?

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  19. What is the difference in the structures of Cl^35 and Cl^37 nuclei?

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  20. What is the relation between the atomic number (Z) and the mass number...

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