A lift raises 50 passengers each having average weight 600 ~N to a height of 100 ~m at a constant speed in time t . If the average power of 15 ~kW is required by the lift, then the value of t in seconds is

Step-by-step solution

We know that, Power = Work done Time P= W t = F s t P= m g h t ...(i) Here, weight of passengers =m g=50 600 ~N height, h=100 ~m Power, P=15 ~kW =15 1000 ~W So from eq. (i) we have, t= m g h P = 50 600 100 15 1000 t=200 ~s