Question

the engine of train moving with uniform acceleration passes an electric Pole with velocity u and the last compartment with velocity v ,the length of train that has passed the pole when the veolity is v+u/2 if the total length of train is l​

Answer 1

Answer: √u2+v2 / 2

Explanation:

Let the length of the train be =l

We apply the equation of motion

v2=u2+2al

2al=v2−u2

The acceleration is a=v2−u22l

For, half the train, the length is =l2 and the

velocity is =w

Therefore,

w2=u2+2a⋅l2

=u2+al

=u2+v2−u2 / 2l x l

=2u2+v2−u2 / 2

=u2+v22

So,

w=√u2+v2 / 2