#### Question

A boy has to lift a load of mass 50 kg to a height of 1 m. (a) what effort is required if he lifts it directly? Take g = 10 N kg-1 (b) If the boy can exert a maximum effort of 250 N, so he uses an inclined plane to lift the load up. What should be the minimum length of the plank used by him?

#### Solution

Mass of load m = 50 kg

Force required to lift a load 1 meter (h) = mxg = 50x10 = 500N

The maximum effort exerted by boy E =250 N

Load L = 500N

Mechanical advantage M.A = `"𝑙𝑜𝑎𝑑"/"𝑒𝑓𝑓𝑜𝑟𝑡"` = `500/250` = 2

M.A = `"𝐼"/"ℎ"`

Height (h) =1m

Minimum length of plank l = MA x h = 2x1 = 2m

Is there an error in this question or solution?

Solution A Boy Has to Lift a Load of Mass 50 Kg to a Height of 1 M. (A) What Effort is Required If He Lifts It Directly? Take G = 10 N Kg-1 (B) If the Boy Can Exert a Maximum Effort of 250 N, So He Uses an I Concept: Concept of Machines Numercials.