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olasank [31]
1 year ago
10

The half life of a substance is defined as the time required for the substance to decrease by half. If the weight of a substance

begins at 128 grams, and the half life is 7 years, what will be the weight of the substance after 28 years?
Mathematics
1 answer:
nexus9112 [7]1 year ago
8 0

the weight of the substance after 28 years is 8 grams.

<h3>How to determine the amount</h3>

We have that the half life of a substance is defined as the time required for the substance to decrease by half

The formula for calculating the half - life of a material is given as;

N(t) = N0 (\frac{1}{2} )^\frac{t}{t^\frac{1}{2} }

Where

  • N(t) is final amount
  • No is the initial amount = 128 grams
  • t1/2 is the half life = 7 years
  • t is the time elapsed = 28 years

Substitute into the formula

N(t) = 128 × (0. 5) ^28/ 7

N (t) = 128 × ( 0. 5) ^ 4

N(t) = 128 × 0. 0625

N(t) = 8 grams

Thus, the weight of the substance after 28 years is 8 grams.

Learn more about half life here:

brainly.com/question/26148784

#SPJ1

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