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4 years ago

There is a 50 g sample of Ra-229. It has a half-life of 4 minutes.

Physics

1 answer:

Sloan [31]4 years ago

4 0

Via half-life equation we have:

$A_{final}=A_{initial}(\frac{1}{2})^{\frac{t}{h} }$

Where the initial amount is 50 grams, half-life is 4 minutes, and time elapsed is 12 minutes. By plugging those values in we get:

$A_{final}=50(\frac{1}{2})^\frac{12}{4}=50(\frac{1}{2})^{3}=50(\frac{1}{8})=6.25g$

There is 6.25 grams left of Ra-229 after 12 minutes.

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3 years ago

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Please help. I don’t understand this

skad [1K]

The short answer is that the displacement is equal tothe area under the curve in the velocity-time graph. The region under the curve in the first 4.0 s is a triangle with height 10.0 m/s and length 4.0 s, so its area - and hence the displacement - is

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Another way to derive this: since velocity is linear over the first 4.0 s, that means acceleration is constant. Recall that average velocity is defined as

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3 years ago

Mr. Miles zips down a water-slide starting at 15 m vertical distance up the scaffolding. Disregarding friction, what is the velo

lilavasa [31]

Answer:

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Explanation:

It is given that,

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So, the velocity of the Mr. miles is 17.14 m/s. Hence, this is the required solution.

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3 years ago

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melisa1 [442]

Answer:

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3 years ago

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Alisiya [41]

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4 years ago