Question

A 300 kg piano is being lowered into position by a crane while two people steady it with ropes pulling to the sides. Bob's rope pulls to the left, 11 ∘ below the horizontal, with 330 N of tension. Ellen's rope pulls toward the right, 28 ∘ below the horizontal.

Part A

What tension must Ellen maintain in her rope to keep the piano descending vertically at a constant speed?

Express your answer in newtons.

Part B

What is the tension in the vertical main cable supporting the piano?

Express your answer in newtons.

Answer 1

Since the pulling Forces are actin at angles,we have to resolve them into their components.

Part A

What tension must Ellen maintain in her rope to keep the piano descending vertically at a constant speed?

So the piano should not veer(change direction) right or left.It should descend vertically downwards.

That means Net force along horizontal direction must be zero(balanced).

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ANSWER:

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Part B

What is the tension in the vertical main cable supporting the piano?

Given the piano should descending vertically at a constant speed.

So acceleration in vertical direction is Zero

Net Force =Mass*acceleration =0

Net Force =Zero

Consider Forces in y direction

ANSWER:

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