# Physics

posted by .

A motorist traveling with a constant speed of 15m/s passes a school-crossing corner, where the speed limit is 10m/s. Just as the motorist passes, a police officer on a motorcycle at the corner starts off in pursuit with constant acceleration of 3m/s^2. (a)How much time elapses before the police catches up the motorist? (b)What is the officer's speed limit at that point? (c)What is the total distance each vehicle has traveled at that point?

• Physics -

a. they both go the same distance.
distancecar=15*t
distanccop=1/2 * 3*t^2 set them equal, solve for t.

distance= 15t

• Physics -

1. A motorist travelling 45 m/s [ abaout 75 mi/h] passes a stationary motorcycle police officer. 2,5 second after motorist passes, the police officer sarts to move and accelerates in pursuit of the speeding motorist. The motorcycle has constant acceleration of 3,6 m/s2.
a) How fast will the police officer be travelling when he overtakes the car ?draw curves of x versus t for both the motorcycle and the car, taking t-0 at the moment the car passes the stationary police officer.
b) Suppose that for reason of safety the policeman does not exceed a maximum speed of 45 m/s [about 100mi/h]. how long will it then take him to overtake the car, and how far will he have traveled ?