A 1000-kg automobile enters a freeway on-ramp at 20 m/s and accelerates uniformly up to 40 m/s in a time of 10 seconds.How far does the automobile travel during that time?
A)100 m
B)200 m
C)300 m
D)400 m
E)none of these

Question

Quizplus · Accepted Answer

We can use the equation:

d = vit + 1/2at^2

where

vi = initial velocity = 20 m/s 
vf = final velocity = 40 m/s 
t = time = 10 s 
a = acceleration

To find the acceleration, we can use:

a = (vf - vi)/t = (40 - 20)/10 = 2 m/s^2

Now we can substitute the values:

d = 20(10) + 1/2(2)(10)^2 
d = 200 + 100 
d = 300 m

Therefore, the automobile travels 300 meters during that time.

A 1000-Kg Automobile Enters a Freeway On-Ramp at 20 M/s