Suppose you walk across a room of length ` 9 m` with a velocity of one and a half kilometre per hour . Express this velocity in `m//s` and find the time you will take to move across the room.

Options

A. 20.6 s
B. 21.6 s
C. 22.6 s
D. 23.6 s

Answer

B

Explanation

Here, distance, s = 9 m
velocity `v= 1.5 km //h =(1.5 xx1000 m)/(60xx60s)=0.417 m//s`
As `v=(s)/(t )` or `t=(s)/(v)=(9)/(0.417)=21.6 s`