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A plank of length 4 m is inclined to t...

A plank of length 4 m is inclined to the ground such that its one end is resting on the ground and the other end is 1 m above ground level. Calculate the effort that has to be applied to push a load of 48 N up the plank.

Text Solution

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Length of the plank l = 4 m.
Height of the inclined plane, h = l m.
Mechanical advantage of the inclined plane is
`M.A. =(l)/(h)=(4m)/(1m)`
M.A. = 4
By definition, M.A. is equal to `=("load (L)")/("effort (E) ")`
`rArr 4 = (48N)/(E)`
`:. E = (48N)/(4)`
`E = 12N`
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