The plank is 3.6 metres long. It is being used as a lever to lift a 40-kilogram box. This represents a load of 400 newtons.
(a) If the fulcrum were placed in the centre of the plank, what downward effort would the man on the right need to apply to raise the box?
(b) If the man wants to push down on the end of the plank with an effort only of 200 newtons:
(i) how far along the plank should the fulcrum be
(ii) what would the mechanical advantage of the lever be?