# 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) s1= vt - for motorist
s2= (1/2)*a*t^2 - for police officer

when the cop cathes up the motorist:
s1 = s2

So vt = (1/2)*a*t^2
15*t= (1/2)*3*t^2
t = 15*2/3 = 10 sec
b) v = u + a*t
= 0 + 3*10 = 30 m/s
c) distance s1=s2= 15*10 = 150m

## Similar Questions

1. ### Physics

A motorist drives along a straight road at a constant speed of 16.5 m/s. Just as she passes a parked motorcycle police officer, the officer starts to accelerate at 3.50 m/s2 to overtake her. Assume that the officer maintains this acceleration. …
2. ### physics

A motorist drives along a straight road at a constant speed of 15.0 m/s. Just as she passes a parked motorcycle police officer, the officer starts to accelerate at 2.00 m/s2 to overtake her. Assuming the officer maintains this acceleration, …
3. ### physics

A speeding motorist traveling 125 km/h passes a stationary police officer. The officer immediately begins pursuit at a constant acceleration of 11.2 km/h/s (note the mixed units). (a) How much time will it take for the police officer …
4. ### physics

A motorist drives along a straight road at a constant speed of 15.0 m/s. just as she passes a parked police officer,the officer starts to accelerate at 2.00 m/s^2 to overtake her. assuming the officer maintains this acceleration, a) …
5. ### physics

A motorist drives along a straight road at a constant speed of 15.0 m/s. just as she passes a parked police officer,the officer starts to accelerate at 2.00 m/s^2 to overtake her. assuming the officer maintains this acceleration, a) …
6. ### Physics

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 …
7. ### mitx 8.01x Classical Mechanics

A motorist traveling with constant speed of vc = 17.000 m/s passes a school-crossing corner, where the speed limit is 10 m/s. Just as the motorist passes, a police officer on a motorcycle stopped at the corner starts off in pursuit. …
8. ### physics

A motorist traveling with constant speed of vc = 16.0 m/s passes a school-crossing corner, where the speed limit is 10 m/s. Just as the motorist passes, a police officer on a motorcycle stopped at the corner starts off in pursuit. …
9. ### physics

1.A motorist drive along a straight road at a constant speed of 15.0 m/s.Just as she passes a parked motorcycle police officer,the officer starts to accelerate at 2.0 m/s^2 to overtake her. Assuming the officer maintains this acceleration, …
10. ### physics

1.A motorist drive along a straight road at a constant speed of 15.0 m/s.Just as she passes a parked motorcycle police officer,the officer starts to accelerate at 2.0 m/s^2 to overtake her. Assuming the officer maintains this acceleration, …

More Similar Questions