Question

an elevator descends into a mine shaft at the rate of 6m/min if the descent starts from 20 m above the ground level, how long will it take to reach -370 m

Answer 1

The rate of 6m/min means that, in every minute, it goes down by 6m

We have 20 above the ground and 370 m below the ground

Note:

-370 m, means it is 370 m below the ground

Total distance = 20 + 370

                       = 390 m


Time taken = 390/6

                  = 65 minutes

OR


1 hour 5 minutes

Answer 2

Answer:

65 minutes or 1 hour and 5 minutes.

Step-by-step explanation:

Given, descending speed of elevator = 6m/min

Descends starts from 20 m above the ground level.

To find the time required to reach 370 m below ground level.

Here, since  the descend starts from 20 m above ground level, the elevator will have to cover an extra distance of 20m. So, total distance = 370 + 20 = 390 m.

Speed = 6m/min

Total distance = 390 m

So, total time taken = total distance/speed

⇒ time = 390/6

⇒ time = 65 minutes

Hence, time required to go 370 m below ground level when the elevator starts from 20 m above, is 65 minutes or 1 hour and 5 minutes.