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प्रश्न
Consider a quantity of a radioactive substance. The fraction of this quantity that remains after t half-lives can be found by using the expression 3–t. What fraction of substance remains after 7 half-lives?
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उत्तर
Since, 3–t expression is used for finding the fraction of the quality that remains after t half-lives.
Hence, the fraction of substance remains after 7 half-lives will be equal to 3–7 i.e., `1/3^7`.
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संबंधित प्रश्न
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“I would like you to place 1 rupee on the first square of my chessboard, 2 rupees on the second square, 4 on the third square, 8 on the fourth square, and so on, until you have covered all 64 squares. Each square should have twice as many rupees as the previous square.” The king thought this to be too less and asked the farmer to think of some better reward, but the farmer didn’t agree.
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| Position of Square on chess board |
Amount (in Rs) |
| 1st square | 1 |
| 2nd square | 2 |
| 3rd square | 4 |
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