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2 years ago

7

what two objects have stored energy? A. ball rolling on the ground B. a small rock sitting on top of a big rock C. a stretched r

ubber band D. a stone lying on the ground

2 answers:

Verizon [17]2 years ago

8 0

The correct statements are:

B. a small rock sitting on top of a big rock

As the rock is at a height with respect to ground it has potential Energy

and

C. a stretched rubber band

A stretched rubber band has elastic potential energy

The others are actually moving and hence would consist of Kinetic energy. Potential energy is stored in objects that do not move and are stationary.

Dmitry_Shevchenko [17]2 years ago

6 0

C and as other have expained below, B as well

Potential energy basically means something has the possibilty to change. A <em>stretched</em> rubber band could be released at any moment, which would then create kinetic energy. If the band wasn't stretched it wouldn't have any potential energy.
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2 years ago

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2 years ago

What is the final temperature when a 3.0 kg gold bar at 99 0C is dropped into 0.22 kg of water at 25oC?

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A heat engine accepts 200,000 Btu of heat from a source at 1500 R and rejects 100,000 Btu of heat to a sink at 600 R. Calculate

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To solve the problem it is necessary to apply the concepts related to the conservation of energy through the heat transferred and the work done, as well as through the calculation of entropy due to heat and temperatra.

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2 years ago

One end of a string is fixed. An object attached to the other end moves on a horizontal plane with uniform circular motion of ra

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Answer:

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$R$ - Radius of rotation, measured in meters.

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2 years ago