Question

A pulley system has a mechanical advantage of 10.

A. If a mover used this pulley to lift a piano with a force of 1450 N a distance of 4 m, how much force must the mover use?
B. How far will eh mover pull the rope?
C. How many ropes support the piano?

Answer 1

(a) 145 N

(B) 40 N

(c) 10 ropes

Step-by-step explanation:

Mechanical advantage,
`MA=\frac {F_i}{F_o}` where
`F_i` and
`F_o` are input and output force respectively

Since MA is given as 10 and input force is 1450 N

`F_o=\frac {F_i}{MA}=\frac {1450 N}{10}=145 N`

Therefore, the mover must use a force of 145 N

(b)

Since also
`MA= \frac {L_e}{L_r}` and the
`L_r` is given as 4 m then

`L_e=L_r* MA= 4 m* 10= 40 m`

(c)

Literally, we need 10 rope segments to support the piano since we utilize the mechanical advantage