Question

A coolie uses a sloping wooden plank of length 2.0 m to push up a drum of mass 100 kg into the truck at a height 1.0 m.
(a) What is the mechanical advantage of the sloping plank?
(b) How much effort is needed to push the drum up into the truck?
What assumption have you made in arriving at the answer in part (b) above?

Answer 1

Length of sloping wooden plank l =2.0m

Load =100kgf

Height of inclined plane h =1m

(a) The mechanical advantage of the slopping plank

M.A = `"𝐼"/"ℎ"`= `2/1` = 2

(b) Effort needed to push the drum up into the truck =
Effort = 𝐿𝑜𝑎𝑑𝑀.𝐴= 1002=50 𝑘𝑔𝑓
Assumption: There is no friction between the drum and the plank.