Question

The same retarding force is applied to stop a train. The train stops
after 80 m. If the speed is doubled, then the distance will be

Answer 1

Answer:

320 m

Explanation:

let assume the retarding acceleration on train by force is 'a'.

Now in case 1

by using the equation v^2 - u^2 = 2as

we get the value of u (initial velocity) = 8 root 10

Now in case 2 (when velocity is doubled)

now velocity is doubled, so initial velocity of train becomes 16 root 10

by using the equation v^2 - u^2 = 2as

we get the value of displacement = 320 m

note: as given in the question retardation is same in both cases.