Question

1. Suppose a boy walks across a room which is 15 m in length with a velocity
of one and a half kilometres per hour, find the time he will take to walk
across the room.​

Answer 1

Answer:

Displacement=9 m

Velocity= 1.5 km/ hr

1 \frac{km}{hr} = \frac{1000 m}{60 * 60 sec} = (1000/3600)m/s

=5/18 m/s

To convert km/hr to m/s , just multiply the given value of km/hr by 5/18

1.5 km/hr = 1.5×5/18 = 0.4166 m/s

velocity=displacement/Time

Time=Displacement/velocity

=9/0.4166

=21.603 sec