If a man pushes pushes a drum of oil of 10 kg up and incline OA, if OA is 5m and AB is 3m.

What work is done by the man?
What work is done if the drum is just lifted from b to a??

3 answers

If it goes up 3 meters
then the gain in potential energy is m g h = 10 * 9.81 (on earth) * 3 Joules
Either way that is the amount of work done if no energy is lost to friction or radiation or whatever.
Now if you did not realize that the you would figure
the Force exerted by the man is m g sin( incline angle
= m g (3/5)
and he pushed for 5 meters
so
m g * (3/5) = 5 = m g * 3 = m g h like we said before
typos
m g * (3/5) * 5 = m g * 3 = m g h like we said before