Karnataka Board PUCPUC Science 2nd PUC Class 12

A Freshly Prepared Radioactive Source of Half-life 2 H Emits Radiation of Intensity Which is 64 Times the Permissible Safe Level. the Minimum Time After Which It Would Be Possible - Physics

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MCQ

A freshly prepared radioactive source of half-life 2 h emits radiation of intensity which is 64 times the permissible safe level. The minimum time after which it would be possible to work safely with this source is

Options

  • 6 h

  • 12 h

  • 24 h

  • 128 h.

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Solution

12 h

A freshly prepared radioactive source emits radiation of intensity that is 64 times the permissible level. This means that it is possible to work safely till 6 half-lives (as 26 = 64) of the radioactive source. Since the half-life of the source is 2h, the minimum time after which it would be possible to work safely with this source is 12 h.

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Chapter 24: The Nucleus - MCQ [Page 441]

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HC Verma Class 11, Class 12 Concepts of Physics Vol. 2
Chapter 24 The Nucleus
MCQ | Q 14 | Page 441

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