Question

A 50,000 kg train is rolling on its own down the track at 5 m/s. You grab the rope trailing behind it, and exert a stopping force of 2000 N. How long does it take to stop the train?

Answer 1

Answer:

t = 125 seconds

Explanation:

Given that,

The mass of a train, m = 50,000 kg

Initial speed, u = 5 m/s

Stopping force, F = 2000 N

We know that,

Force, F = ma

Where

a is acceleration

$F=\dfrac{m(v-u)}{t}\\\\t=\dfrac{m(v-u)}{F}\\\\t=\dfrac{50000(0-5)}{-2000}\\\\t=125\ s$

So, it will take 125 seconds to stop the car.