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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 circular horizontal surface having an area of 1020.5 mm2that is completely immersed in a fluid experiences a uniform force of

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3 years ago

An irregular object of mass 3 kg rotates about an axis, about which it has a radius of gyration of 0.2 m, with an angular accele

Citrus2011 [14]

Answer:

The magnitude of the applied torque is $6.0\times10^{-2}\ N-m$

(e) is correct option.

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Given that,

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$\tau=I\times\alpha$

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3 years ago

Squids and octopuses propel themselves by expelling water. They do this by keeping water in a cavity and then suddenly contracti

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Answer:

The speed of water must be expelled at 6.06 m/s

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The minus sign indicates the velocity of the water is opposite the velocity of the octopus.

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3 years ago

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4 0

3 years ago

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What is the wavelength of violet light that has a frequency of 7.5x10^14

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Λ= V/f
but change it to represent the speed of light, c 
λ= c/f 
c = 3.00 x 10^8 m/s 
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3 years ago

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