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Question:
When the mass of a sample of a radioactive substance decreases, the mean life of the sample:

1.increases

2.decreases

3.remain unchanged

4.first decreases then increases

Posted Date:-2021-12-17 10:46:36

More MCQS Questions and answers

  1. According to Yukawa’s theory of nuclear forces, the origin of nuclear force between nucleons is due to the exchange of
  2. Alpha particle emitted from a radioactive material are:
  3. An alpha particle is emitted from 88Ra226, then the product nuclei has:
  4. An electron and a positron each having a mass equivalent to 0.53 MeV annihilate each other and produce a photon. The minimum energy of the photon is.
  5. Chadwick was awarded the Nobel prize in Physics in 1935 for his discovery of:
  6. Energy of electron in the 1st orbit of H-atom is:
  7. Fusion takes place at high temperature because:
  8. How many electrons are contained in 23892U nucleus?
  9. If radio active nuclei emits β-particle, then mass-number:
  10. Nuclear force is:
  11. Rutherford is the unit of:
  12. The Bohr model of atom:
  13. The density of a nucleus is of the order of:
  14. The ground state energy of Hydrogen atom is -13.6 eV. What is the potential energy of electron in this state?
  15. The half life of a radioactive decay is n times its mean life, n is equal to:
  16. The helium atom does not contain
  17. The mass no. of a nucleus is M and its atomic no. is Z. The number of neutrons in the nucleus is :
  18. The more readily fissionable isotope of uranium has an atomic mass of:
  19. The phenomena of radioactivity is:
  20. What percentage of radioactive substance is left after 5 half lives?
  21. When the mass of a sample of a radioactive substance decreases, the mean life of the sample:
  22. X-ray was discovered by :
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