Question

An elevator descends at the rate of 5 m/min. If the elevator is present at 20 m above the ground level, how long will it take to reach – 125 m. *

Answer 1

$\huge\bold{\textbf{\textsf{{\color{cyan}{Answer}}}}}$

Total distance elevator has to travel = Initial position - final position

$= 10 - ( - 350) \\ = 10 + 350 \\ = 360m$

Now,

Elevator descends at rate 6m/min

∴ Elevator travels 6 m in = 1 minute

Elevator travels 1m in $= \frac{1}{6} minutes$

Elevator travels 360m in $= \frac{1}{6} \times 360 \: minutes \\ = 60 \: minutes \\ = 1 \: hour$

∴ It will take the elevator 1 hour .

Answer 2

Step-by-step explanation:

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 = 265/5

53min.