Question

A multistorey building has 25 floors above the ground level each of height 5 m. It also has 3 floors in the basement each of height 5 m. A lift in building moves at a rate of 1 m/s. If a man starts from 5 0m above the ground, how long will it take him to reach at 2nd floor of basement?

Answer 1

Man covers the distance above the ground = 50 m

And man covers the distance below the ground = 2 × 5 = 10 m   ......[∵ Distance between two floors = 5 m]

Thus, total distance = 50 m + 10 m = 60 m

∵ Speed of the lift = 1 m/s  ......[Given]

Hence, time taken to reach second floor of basement = `"Distance"/"Speed"`

= `(60  m)/(1  m/s)`

= 60 s or 1 min