Question

A person is running at a maximum speed of 3 ms-1 along the length of a train to catch hold

of the door of a compartment. When he is just 2.5 m from the door, the train steams off with an

acceleration of 1 ms-2

. Find how long it takes him to catch the door?​

Answer 1

Answer:

The time taken by the man to catch the train is 2 seconds

Let the time taken by the person to catch the train is t

In time t if the train covers d distance then the man has to cover distance = (d+6) m

Since man moves with constant speed of 4 m/s

Therefore,

d + 6=4*t

Again since the train starts from rest with constant acceleration of 1 m/s²

Therefore, using the second equation of motion

So here we are getting two values of t, both are valid

Since in 2 seconds the person will reach the gate

Therefore, the person will catch the train in 2 seconds

If he doesn't catch the train and keep running then due to the acceleration of the train, the speed of the train will keep increasing and then again the door of the compartment will be surpassing him after 6 seconds.

Hope this answer is helpful.

Explanation: