Question

1. A train is moving north at 5 m/s on a straight track. The engine is causing it to accelerate northward at 2 m/s^2.

How far will it go before it is moving at 20 m/s?
A) 83
B) 43
C) 39
D) 94
E) 20

Answer 1

It will go up to 93.75 m before it is moving at 20 m/s

Step-by-step explanation:

As we know that

`v^2 - u^2 = 2aS`

here v is the final speed i.e 20 m/s

u is the initial speed i.e 5 m/s

a is the acceleration due to gravity i.e 2 m/s^2

Substituting the given values in above equation, we get -

`20^2 - 5^2 = 2*2*S\\S = 93.75`meters