Question

The elevator that takes passengers from the lobby of the John Hancock Centre in

Chicago to the observation level travels 300 feet in 5 seconds. The observation level
is located on the 100th floor, at 1200 feet above the ground. Find the time it takes
the elevator to travel from the lobby to the observation level. (4)

Answer 1

20 seconds

Explanation:

s = Distance traveled by elevator = 300 ft

t = Time taken = 5 seconds

Velocity is given by

`v=(s)/(t)\\\Rightarrow v=(300)/(5)\\\Rightarrow v=60\ \text{ft/s}`

Distance to the observation level from the lobby = 1200 ft

Time taken is given by

`t=(1200)/(60)\\\Rightarrow t=20\ \text{s}`

Time taken to reach the observation level from the lobby is 20 s.