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2 years ago

10points asap A force of 30 N acts upon a 7 kg block. Calculate its acceleration.

1 answer:

5 0

Hello! Assuming that the only force acting on the mass is 30N...

Fnet = 30N
Fnet = ma (mass x acceleration)
ma = 30N
a = 30N / m
a = 30N / 7kg
a = 4.2857 m/s^2
a = 4 m/s^2

I hope this helps!

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3 years ago

For exercise, an athlete lifts a barbell that weighs 400 N from the ground to a height of 2.0 m in a time of 1.6 s. Assume the e

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Answer:

Explanation:

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b )

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3200 J

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d )

1 ) Since he is doing same amount of work , his metabolic energy output is same as that in earlier case .

2 ) Since he is doing the same exercise in less time so his power is increased . Hence in the second day his power is more .

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3 years ago

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