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3 years ago

HELP QUICK numbers 2-6

Physics

2 answers:

Sindrei [870]3 years ago

5 0

Answer:

2. B

3. A

4. C

5. B

6. A

Explanation:

2. Sound waves use vibrating molecules to move. With this being said, sound waves would travel best through dense materials, and would travel worst in empty materials, like space. Using this information, you can infer that B would be the answer because water is denser than air and water is the densest material on that list.

3. The speed of the wave is equal to the frequency times the wavelength. Since it has a wavelength of 100 meter and 20 Hertz, the speed would 2000 m/s

4. Like noted in question 2, sound waves travel best in dense materials. Rock is the densest material in that last.

5. By looking at the chart, you can see that the speed increases by 4 m/s when the temperature increases by 10. Using simple division, you could determine that the speed would go up by 2 m/s since the jump between 15 degrees and 20 degrees is 5, which is half of 10, making the speed half of 4.

6. The speed would decrease because, like stated above, sound travels best through dense materials. Since rock is denser than air, the speed would decrease as it leaves.

White raven [17]3 years ago

3 0

B,A,C,B,A Just took the test myself

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so its speed for round trip will be

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3 years ago

I. The spring does work on the box from the moment the box first hits the spring to the moment the spring first reaches its maxi

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Hope this helped. :)

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3 years ago

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Answer:

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4 years ago

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Answer:

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Explanation:

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The mechanical energy is conserved in the presence of the following conservative forces :

-- electrostatic forces

-- magnetic forces

-- gravitational forces

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