Question

A train is moving at a velocity of 25 ms-1
. It is brought to rest by applying the
brakes which produces a uniform retardation of 0.5 ms-2
. Calculate
(i) the velocity of the train after 10 s
(ii) If the mass of the train is 20000 kg then calculate the force required to
stop the train.
[

Answer 1

Hey!

So this can be solved using kinematic equations.

Vi = 25m/s

a = -0.5m/s^2

(i) In order to find the final velocity we can use the equation

vf = vi +at

vf = (25) - (0.5)(10)

vf = 20 m/s

After 10 seconds the train is going at 20 m/s

(ii) Well the acceleration is given to us, and the mass as well. We can use Newton's second law to solve this.

F = ma

F = 20000(-0.5)

F = -10,000 N

The force is negative because you need to apply a force in the opposite direction of motion to stop the car.

Answer 2

Answer:

(i)v=u+at

=25+(-0.5)*10

=25-5

=10m/s

(ll)force=mass*acceleration

=20000*(-0.5)

=-10000 N (minus symbol suggests force acting in opposite direction)....

Explanation:

plz mark it the brainliest......

plz follow me...