Post a New Question

Physics

posted by .

A police car traveling at 94.5 km/h is traveling west, chasing a motorist traveling at 77.2 km/h.
(a) What is the velocity of the motorist relative to the police car?
The magnitude and its direction

(b) What is the velocity of the police car relative to the motorist?
The magnitude and its direction

(c) If they are originally 250 m apart, in what time interval will the police car overtake the motorist?

A full working would be appreciated! thanks!

  • Physics -

    a. Vm = 77.2 - 94.5 = -17.3 km/h.

    b. Vp=94.5 - 77.2=17.3 km/h=Velocity of policeman.

    c. Vm*t=X km=Dist traveled bymotorist.
    Eq1: 77.2t = X.

    Vp*t = (X+250)=Dist. traveled by police.
    Eq2: 94.5t = X+0.250)km.
    In Eq2, substitute 77.2t for x:
    94.5t = 77.2t + 0.2525
    94.5t - 77.2t = 0.25
    17.3t = 0.25
    t = 0.01453 h. = 0.87 min = 52.3 s.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Physics

    Car A is traveling at 84 km/h while Car B is traveling at 58 km/h. What is the relative velocity of Car A to Car B if they both are traveling in the same direction?
  2. Physics

    Car A is traveling at 84 km/h while Car B is traveling at 58 km/h. What is the relative velocity of Car A to Car B if they both are traveling in the same direction?
  3. PHYSICS-URGENT HELP

    A stationary police car emits a sound of frequency 1200 Hz that bounces off of a car on the highway and returns to the police car with a frequency of 1250 Hz. The police car is right next to the highway, so the moving car is traveling …
  4. Physics

    A motorist travelling at 107 km/hr is being chased by a police car at 133 km/hr. If the police car starts from 3.0 km back, how long does it take to catch the motorist?
  5. Physics

    A motorist traveling at 30 m/s passes a parked police car. At the instant the motorist passes the police car, the police car starts chasing the motorist with an acceleration of 3 m/s^2. How far does the police car have to travel to …
  6. physics

    a drunken motorist who is moving at a constant velocity of 90 km/h passes a stationary police patrol car. The patrol car immediately gives chase at a constant acceleration and catches up with the motorist after a distance of 10 km. …
  7. physics

    A motorist travelling at 82 km/hr is being chased by a police car at 121 km/hr. If the police car starts from 4.0 km back, how long does it take to catch the motorist?
  8. Math

    A motorist traveling 55 mph is being pursued by a highway patrol car traveling 65 mph. If the patrol car is four miles behind the motorist, how long will it take the patrol car to overtake the motorist?
  9. Physics

    A speeding motorists passes a stopped police car. At the moment he passes, the police car begins accelerating at a constant rate of 4.4 m/s^2. The motorist unaware that he is being chased, continues at a constant speed until the police …
  10. Physics

    An unmarked police car traveling a constant 90 km/h is passed by a speeder traveling 128 km/h. Precisely 1.00 s after the speeder passes, the police officer steps on the accelerator; if the police car's acceleration is 2.80 m/s2 , …

More Similar Questions

Post a New Question