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. 216s
B. 21.6s
C. 2.16s
D. 1.15s

Answer

B

Explanation

Here , distance , `s = 9 m`,
Velocity , `v = 1.5 km//h = ( 1.5 xx 1000 m)/( 60 xx 60 s) = 0.417 m//s , t = ?`
As `v = (s)/( v) , t = (s)/(v) = ( 9) /( 0.417) = 21.6 s`