Question

A speeding train slams on the brakes when it sees a car is on the tracks in front of it. It takes the train 25 seconds for it to go from an initial speed of 75 m/s to come to a complete stop. What is the train’s acceleration?

Answer 1

Step-by-step explanation:

Given:

Initial Velocity is 75 m/s

Fianl Velocity: 0 m/s

Time 25 seconds.

Acclereation?

Use kinematic equation,

`v _(f) = v _(i) + at`

`0 = 75 (m)/(s) + a(3s)`

`{ - 75} (m)/(s) = 3s(a)`

`- {25} \frac{m}{ {s}^(2) } = a`

So the acclereation is -25 m/s^2. Since the Velocity is positive and acclereation is negative, the train will be slowing down.