Question

The elevator descends at the rate of 5m/ Mon. If the descent stars from 50 m above the ground level, find the time taken by the elevator to reach - 250 m

Answer 1

EXPLANATION.

• GIVEN

Elevator descends at a rate of 5 m/min

if the descends starts from 50 m above ground

level.

To find the time taken by the elevator toreach -250 m.

According to the question,

Total distance elevator has to travel =

=> initial position - final position

=> 50 - ( -250)

=> 300 m

Now,

Elevator descends at rate = 5 m/min

Elevator travel 5 m in = 1 minute.

Elevator travel 1 m = 1/5 minute.

Elevator travel 300 m in = 1/5 X 300

=> 60 minute = 1 hour.

Therefore,

It will take the elevator = 1 hour.

Answer 2

$\large\bf{ \underline{ \underline \red{Given:-}}}$

• The elevator descends at the rate of 5m/min

• The descent starts from 50m above the ground level.

$\large\bf{ \underline{ \underline \blue{To\:Find}}}$

• The time taken by the elevator to reach -250m

$\large\bf{ \underline{ \underline \green{Solution:-}}}$

• Initial height = 50m

• Final depth = -250m

Here we took the final depth as negative because the elevator is descending ( going down)

Total height descent by the elevator
= 50- (-250)

= 300m

As the elevator descends at 5m/min

Time taken by the elevator to descend 5m = 1 minute

Time taken by the elevator to descend 1m = 1/5 min

Therefore:-

Time taken by elevator to descend -300m

$= \sf \dfrac{ 300}{ 5}$

$\sf = 60min$

60min = 1hour.

Therefore:-

Time taken by elevator to reach - 250m is 1 hour.