Answer:
η = 0.667 = 66.7%
Explanation:
The efficiency of the man can be given by the following formula:
η = output/input
where,
η = efficiency of man = ?
output = potential energy gain of the box = Wh
input = work done by man = Fd
Therefore,
[tex]\eta = \frac{Wh}{Fd}[/tex]
where,
W = weight of box = 200 N
h = height gained by box = 1 m
F = force exerted by man = 60 N
d = length of ramp = 5 m
Therefore,
[tex]\eta = \frac{(200\ N)(1\ m)}{(60\ N)(5\ m)}[/tex]
η = 0.667 = 66.7%
