A car moving along a straight road at 30m/s slows uniformly to a speed of 10m/s in a time of 5s. determine the
(a) acceleration of the car
(b) distance it moves during the third second

A=ACCELERATION = -4 m/s^2

B=DISTANCE= 72 m

Explanation:

Solving for the acceleration of the car

A= (10 m/s-30 m/s) / 5s

A= -20 m/s / 5s

A= -4 m/s^2

Solving for the distance traveled after the third second

D= v1 * t + 1/2at^2

D= 30 m/s * 3 s + -2m/s^2 * (3s)^2

D= 90 m + - 18 m

D = 72 m

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