Question

An elevator descends into a mine shaft at the rate of 5 m/min. If the descent starts from 15 m above the ground level, how long will it take to reach −250 m?

Answer 1

The elevator’s position = 15 m above ground level = +15 m

It should reach = −250 m

The distance to be travelled = 15 – (−250) m = 15 + 250 m = 265 m

Time taken to descend 5 m = 1 min

∴ Time required to descend 265 m = `24/8` = 53 min