Question

A bus covers a certain distance in 60 minutes if it runs at a speed of 60 km/hr. What must be the speed of the bus in order to reduce the time of journey by 40 minutes?

Answer 1

Step-by-step explanation:

Answer is 180km/hr.

It comes from the basic formula

S=d/t

S=speed

d=distance

t=time

In first case s=60km/hr which is constant till it completes the distance so acceleration is o. And it is rectilinear motion .hence we use simple one dimensional motion equation

S=d/t

First we calculate d

t=1hr.

d=s*t

d=60 km

Now again applying this but now t=20 min. i.e 1/3hr because time is reduced by 40 min.

So

S=60km*/(1/3)hr

S=180km/hr.

I hope this works!cheers.