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The half-life of a certain radioactive substance is 6 hours. In other
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28 Jan 2021, 03:08
28 Jan 2021, 03:08
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The half-life of a certain radioactive substance is 6 hours. In other words, if you start with 8 grams of the substance, 6 hours later you will have 4 grams. If a sample of this substance contains x grams, how many grams remain after 24 hours?
A. \(\frac{x}{32}\)
B. \(\frac{x}{16}\)
C. \(\frac{x}{8}\)
D. \(2x\)
E. \(4x\)
Kudos for the right answer and explanation
A. \(\frac{x}{32}\)
B. \(\frac{x}{16}\)
C. \(\frac{x}{8}\)
D. \(2x\)
E. \(4x\)
Kudos for the right answer and explanation
Re: The half-life of a certain radioactive substance is 6 hours. In other
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29 Jan 2021, 01:09
29 Jan 2021, 01:09
1
half-life every 6 hours.
In a simple sentence, the life will be \(\frac{1}{2}\) every six hours.
We're given substance of x gram.
After 6 hours = x * \(\frac{1}{2}\) = \(\frac{x}{2}\)
After 12 hours = \(\frac{x}{2}\) * \(\frac{1}{2}\) = \(\frac{x}{4}\)
After 18 hours = \(\frac{x}{2}\) * \(\frac{1}{2}\) = \(\frac{x}{8}\)
After 24 hours = \(\frac{x}{8}\) * \(\frac{1}{2}\) = \(\frac{x}{16}\)
Answer B
In a simple sentence, the life will be \(\frac{1}{2}\) every six hours.
We're given substance of x gram.
After 6 hours = x * \(\frac{1}{2}\) = \(\frac{x}{2}\)
After 12 hours = \(\frac{x}{2}\) * \(\frac{1}{2}\) = \(\frac{x}{4}\)
After 18 hours = \(\frac{x}{2}\) * \(\frac{1}{2}\) = \(\frac{x}{8}\)
After 24 hours = \(\frac{x}{8}\) * \(\frac{1}{2}\) = \(\frac{x}{16}\)
Answer B
Re: The half-life of a certain radioactive substance is 6 hours. In other
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10 Dec 2023, 12:13
10 Dec 2023, 12:13
1
After 24hours it will break down 24/6 times =4
Therefore
Amount left = x(1/2) ^4 = x/16
Adewale Fasipe, GRE quant instructor from Nigeria.
Therefore
Amount left = x(1/2) ^4 = x/16
Adewale Fasipe, GRE quant instructor from Nigeria.
