Question

If a pulley system with an ideal mechanical advantage of 2 is used in lifting a 2,000 lb. car, how far would the car move if the effort moved 2 ft.?

Answer 1

`1"ft"`

Explanation:

Since work = force x distance and assuming 100% efficiency we can write:

`F_lxxD_l=F_exxD_e`

`:.F_l/F_exxD_l=D_e`

Since `MA=F_l/F_e=2` we can write:

`2xxD_l=D_e=2`

`:.D_l=2/2=1"ft"`