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Mr. Starr pushed a cart full of groceries to his car. After emptying the cart, he pushed it back to the store. He pushed the cart

at a speed of 2 meters per second each way. Which is the best prediction? (1 point)

The cart had the same kinetic energy going each way.

The cart's kinetic energy depends on Mr. Starr's mass.

When it was empty, the cart had less kinetic energy.

When it was full, the cart had less kinetic energy.

User Victwise
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2 Answers

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Answer:

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Step-by-step explanation:

I just completed this assignment UwU

User Bdukes
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4 votes

Answer:

The shopping cart has less kinetic energy when it is empty.

Step-by-step explanation:

When an object of mass
m travels at a speed of
v, the kinetic energy of that object would be
(1/2)\, m\, v^(2).

In this question, the speed of the shopping cart is fixed (
v = 2\; {\rm m\cdot s^(-1)}.) Kinetic energy would be proportional to the mass
m of the shopping cart (including that of its contents.)

The mass of the shopping cart is lower when it is empty on the way back to the store. Therefore, the kinetic energy of the shopping cart would also be lower than when it was full.

User J Blaz
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7.8k points