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3 years ago

HELP!!

Physics

1 answer:

Otrada [13]3 years ago

3 0

Answer:

22 N

Explanation:

The box is moving, so there is kinetic friction.

The speed is constant, so there is no acceleration.

Draw a free body diagram of the box. There are four forces.

Normal force Fn pushing up.

Weigh force mg pulling down.

Applied force F pushing right.

Friction force Fn μk pushing left.

Sum the forces in the y direction:

∑F = ma

Fn − mg = 0

Fn = mg

Sum the forces in the x direction:

∑F = ma

F − Fn μk = 0

F = Fn μk

F = mg μk

F = (11.2 kg) (9.8 m/s²) (0.200)

F = 22.0 N

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A. The second stone hits the ground exactly one second after the first.

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Answer:

Answer is explained in the explanation section below.

Explanation:

Solution:

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