Question

HELP! in 10 seconds, a car accelerates at a rate 4m/s^2 to 60 m/s.

How far has the car traveled?
How fast was it going before it accelerated?

Answer 1

To solve food distance (change in distance, delta x “Δx”), use the fifth kinematic equation.
Δx= vft-1/2at^2
*with this equation, no algebra is necessary, just plug in numbers*
60(10)- (1/2*4*10^2) =400 m
Now we can use this to solve for the initial velocity (vi) using the first kinematic equation
Vf=vi+at
Now use algebra to rearrange to solve for vi
Vi= 2Δx/t-vf
(2*400)/(10-60)=
16 m/s