A student is standing at a distance of 50 metres from the bus. As soon as the bus begins its motion with an acceleration of 1 m/s−2 , the student starts running towards the bus with a uniform velocity u . Assuming the motion to be along a straight road, the minimum value of u , so that the student is able to catch the bus is
Let student will catch the bus after t sec. So it will cover distance ut.
Similarly distance travelled by the bus will be 12at2 for the given condition.
ut=50+12at2=50+t22 [a=1 m/s2]
⇒ u=50t+t2
To find the minimum value of u.
dudt=0,so we get t=10 sec, then u = 10 m/s