A man of mass 85kg stands on a lift of mass 30kg When he pulls on the rope he exerts a force of 400N on the floor of the lift Calculate acceleration of the lift Given g =10 m//s^(2) .

A man of mass 85kg stands on a lift of mass 30kg When he pulls on the

1.	A man of mass 85kg stands on a lift of mass 30kg When he pulls on the rope he exerts a force of 400N on the floor of the lift Calculate acceleration of the lift Given g =10 m//s^(2) .
Answer» Solution :Here mass of man `M = 85kg` Mass of LIFT, `m = 30kg` When pf man PULLS the rope with a force `F=400 N` let the upwards ACCELERATION of the lift be a let `T` be the tension in the rope The equation of motion of the man is `85 a = T +F - Mg` As` F' = F = 400 N` `:. 85 a = T + 400 - 85 xx 10 = T - 450` where `400N` is upward REACTION of floor on the man. The equation of motion of the lift is `30 a = T - 400 - mg - T - 400 - 30 xx 10` `=T - 700` On solving (i) and (ii) we get `a = 4.55m//s^(2)` .