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3 years ago

If a pulley with six supporting ropes is used to lift a 1200 lb piano, what input force is needed?

Physics

2 answers:

Vladimir [108]3 years ago

5 0

Answer:

D) 200 Lb

Explanation:

As we know that the piano is balanced by six ropes connected to it

by the force balance we can say that tension force of all ropes will combined to balance the weight of the object

So here we can say by force equation we will have

$6T = mg$

so we will have

$T = \frac{mg}{6}$

here we know that

$mg = 1200 lb$

so we will have

$T = \frac{1200}{6} = 200 lb$

Lisa [10]3 years ago

3 0

The correct answer is d) 200 lbs.

Hope that I was of help.

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Answer:

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I rename angle (θ) = angle(α)

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This is equation (1)

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We suppose yi = 0

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We need the time in which Vy = 0 m/s so we use (1)

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