Question

A train traveling at 18.2 m/s accelerates to 39.9 m/s over a distance of 1250 m. How long did it take the train to cover this distance?

Answer 1

43.4 s

Step-by-step explanation:

First of all, we can find the acceleration of the train by using the equation:

`v^2 -u^2 = 2ad`

where

v = 39.9 m/s is the final speed

u = 18.2 m/s is the initial speed

a is the acceleration

d = 1250 m is the distance covered

Solving for a,

`a=(v^2-u^2)/(2d)=((39.9 m/s)^2-(18.2 m/s)^2)/(2(1250 m))=0.50 m/s^2`

And now we can fidn the time taken, by using the formula:

`a=(v-u)/(t)\\t=(v-u)/(a)=(39.9 m/s-18.2 m/s)/(0.50 m/s^2)=43.4 s`