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Verizon [17]
3 years ago
5

How much power is required to raise a 100 kg crate a vertical distance of 2 m in a time of 4 s? A. 200 W B. 500 W C. 800 W D. 20

00 W
PLEASE HELP
Physics
1 answer:
Ugo [173]3 years ago
3 0

Power = (work done) / (time to do the work)

Work done = (force) x (distance)

Force = (weight of the crate) = (mass of the crate) x (gravity)


Crate weight = (100 kg) x (9.8 m/s²)

Force = 980 Newtons

Work done = (980 N) x (2 m) = 1,960 Joules

Power = (1,960 Joules) / (4 seconds)

<em>Power = 490 Joules per second</em>

(Whoever wrote the question used 10 m/s² for gravity instead of 9.8 m/s², so his answer came out to be 500 W.  That's <em>choice-B</em> .)

<em>Power = 490 watts</em>

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Answer:

t=1.9 sec

Explanation:

From the question we are told that:

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