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2 years ago

12. In which of the positions shown in the picture, will Joshua have both potential and kinetic energy?

Physics

1 answer:

Zielflug [23.3K]2 years ago

8 0

Answer:

Answer: D. Only R

Explanation:

The Principle Of Conservation Of Mechanical Energy

In the absence of friction, the total mechanical energy is conserved. That means that

Em=U+K is constant, being U the potential energy and K the kinetic energy.

At the top of the path (point Q), Joshua is at rest but his height is at a maximum. Thus his kinetic energy is zero.

At point P, Joshua is at the minimum level (potential energy zero) and his speed is at a maximum.

At point R, Joshua has some height and some speed which means he has both types of energy.

Answer: D. Only R

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Answer: a) 139.4 μV; b) 129.6 μV

Explanation: In order to solve this problem we have to use the Ohm law given by:

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Then we have:

for cooper R=1.71 *10^-8* 1.8/(0.001628)^2= 11.61 * 10^-3Ω

and for silver R= 1.58 *10^-8* 1.8/(0.001628)^2=10.80 * 10^-3Ω

Finalle we calculate the potential difference (V) for both wires:

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3 years ago

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Answer:

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Explanation:

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3 years ago

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Answer:

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Explanation:

I will try to order the solutions from the least correct to the most correct.

Since a temperature greater than 200 ° F is required, that is to say approximately 93 ° c, Polycaprolactone is the least indicated. Its melting point is approximately 60 ° C, so it would not serve the required application.

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3 years ago

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Explanation:

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