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

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

so we will have

here we know that

so we will have