Question

A train is traveling at a speed of

8
0
km
h
80
h
km
​ 80, space, start fraction, k, m, divided by, h, end fraction when the conductor applies the brakes. The train slows with a constant acceleration of magnitude
0
.
5
m
s
2
0.5
s
2

m
​ 0, point, 5, space, start fraction, m, divided by, s, start superscript, 2, end superscript, end fraction. We want to find the distance the train travels from the time the conductor applies the brakes until the train comes to a complete stop.
Which kinematic formula would be most useful to solve for the target unknown?

Answer 1

v^2 =v02 +2aΔx

Step-by-step explanation:

Answer 2

Distance covered by the train, x = 493.72 meters

Step-by-step explanation:

It is given that,

Initial speed of the train, u = 80 km/h = 22.22 m/s

Final speed of the train, v = 0 (it stops)

Acceleration of the train,
`a=-0.5\ m/s^2` (it decelerates)

Let x is the distance the train travels from the time the conductor applies the brakes until the train comes to a complete stop. It can be calculated using the kinematic formula as :

`v^2-u^2=2ax`

`x=(v^2-u^2)/(2a)`

`x=(-(22.22)^2)/(2* -0.5)`

x = 493.72 meters

So, the distance covered by the train from the time the conductor applies the brakes until the train comes to a complete stop is 493.72 meters. Hence, this is the required solution.