A car traveling at a constant speed of 39.6 m/s passes a trooper hidden behind a billboard. One second later the trooper starts the car with a constant acceleration of 2.25 m/s^2

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How long after the trooper starts the chase does he overtake the speeding car?
Answer in units of s

1 answer

Write equations for the distance travelled by each car after the car passes at t = 0. Set the two distances equal and solve for t.

X1 = 39.6 t
X2 = (2.25/2)(t-1)^2

X1 = X2

Solve for t. The time they are asking for is t-1.