Question

An elevator descends into a mine shaft at the rate of 6 m/min. If the descent starts from 10 m above the ground level, how long will it take to reach − 350 m.

Answer 1

Distance descended is denoted by a negative integer.

Initial height = +10 m

Final position= −350 m

Total distance to be descended by the elevator = Initial position - Final position

= (+10) − (−350) = 360 m

Time taken by the elevator to descend 6 m =1 min

Thus, time taken by the elevator to descend 360 m = (360) ÷ (6)

= 60 minutes = 1 hour