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3 years ago

Help with these please someone?

Physics

1 answer:

DIA [1.3K]3 years ago

7 0

Answer:

8. 2.75·10^-4 s^-1

9. No, too much of the carbon-14 would have decayed for radiation to be detected.

Explanation:

8. The half-life of 42 minutes is 2520 seconds, so you have ...

1/2 = e^(-λt) = e^(-(2520 s)λ)

ln(1/2) = -(2520 s)λ

-ln(1/2)/(2520 s) = λ ≈ 2.75×10^-4 s^-1

___

9. Reference material on carbon-14 dating suggests the method is not useful for time periods greater than about 50,000 years. The half-life of C-14 is about 5730 years, so at 65 million years, about ...

6.5·10^7/5.73·10^3 ≈ 11344

half-lives will have passed. Whatever carbon 14 may have existed at the time will have decayed completely to nothing after that many half-lives.

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A 259-kV power transmission line carrying 429 A is hung from grounded metal towers by ceramic insulators, each having a 0.71×109

ella [17]

Answer:

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Explanation:

Given that,

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4 years ago

A train travels 8.81 m/s in a -51.0° direction.

Bad White [126]

The displacement of the train after 2.23 seconds is 25.4 m.

<h3>Resultant velocity of the train</h3>

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where;

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The displacement of the train is the change in position of the train after a given period of time.

The displacement is calculated as follows;

Δx = vt

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Learn more about displacement here: brainly.com/question/2109763

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