Question

a bus is moving with velocity 10 metre per second on a straight road scooter wishes to overtake the bus in 100 seconds if the bus is at a distance of 1 km from the scooter with what velocity scooter should chase the bus

Answer 1

Given:
Time(t)= 100 s , distance (s)=1km= 1000m
Vb=10m/s          (relative speed with respect to the bus)

Velocity (V)=distance /time = 1000/100= 10m/s

Vs= velocity of scooter,  Vb=velocity of bus

V = Vs-Vb         (both bus & scooter are moving in the same direction)
10= Vs-10
10+10 = Vs
20=Vs

Vs=20m/s
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The velocity with which scooterist should chase the bus is20m/s

Answer 2

With relative velocity concept this question is easy to solve.

Relative velocity = Relative distance / Time
(v - 10m/s) = 1000 m / 100 s
v - 10 m/s = 10 m/s
v = 20 m/s
Velocity of scooter should be 20 m/s