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

A 1800 lbs
B 500 lbs
C 300 lbs
D 200 lbs

2 Answers

4 votes

The correct answer is d) 200 lbs.

Hope that I was of help.

User Althea
by
8.4k points
5 votes

Answer:

D) 200 Lb

Step-by-step 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 = (mg)/(6)

here we know that


mg = 1200 lb

so we will have


T = (1200)/(6) = 200 lb

User Mello
by
8.4k points