physics

posted by .

A vehicle with a mass of 2 tons travels on a horizontal road at a speed of 126km/h.The driver notices a donkey at the side of the road and decides to reduce speed. The brakes are applied and the vehicle slows down to 72km/h after 5 seconds. Calculate the acceleration of the vehicle.

  • physics -

    First change the speeds to m/s.
    126 km/h = 35 m/s
    72 km/h = 20 m/s
    Speed change = 20 - 35 = -15 m/s
    Acceleration = (speed change)/(time)
    = -15/5 = -3.0 m/s^2

  • physics -

    How do you convert 126km/h to m/s

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. physics

    The speed limit in a school zone is 38 km/h. A driver traveling at this speed sees a child run onto the road 16 m ahead of his car. He applies the brakes, and the car decelerates at a uniform rate of 8.5 m/s2. If the driver's reaction …
  2. Physics

    A 1100 kg car is moving toward the north along a straight road at a speed of 20.0 m/s. The driver applies the brakes and the car comes to rest in a distance of 140 m. (a) If the road is completely level, what is the constant force …
  3. Physics

    A car is being driven along a country road on a dark and rainy night at a speed of 20 m/s. The section of road is horizontal and straight. The driver sees that a tree has fallen and covered the road ahead. Panicking, the driver locks …
  4. Physics

    a driver sees a horse on the road and applies the brakes so hard that they lock and the car skids to a stop in 24 m. the road is level and the coefficient of kinetic friction between the tires and the road is 0.7. How fast was the …
  5. physics

    A vehicle with a mass of 2 tons travels on a horizontal road at a speed of 126km/h.The driver notices a donkey at the side of the road and decides to reduce speed. The brakes are applied and the vehicle slows down to 72km/h after 5 …
  6. AS Physics

    A driver leaves his car without applying the hand brakes on a road inclined at an angle of 25 degrees. The car starts to roll down the road with the driver chasing from behind after moving a distance of 20 m the speed of the car is …
  7. physics

    a bus is travelling on a horizontal road at a velocity of 126 km/h when the bus driver notices an object in the road. the brakes are applied and the bus is brought to rest over a distance of 150m. the frictional resistance is 2500n …
  8. Physics

    Amotorvehicle of mass 1200kg is travelling along alevel road at 54km/hr.The breaks are then applied and the speed of the vehicle reduced to 18km/hr over adistance of 50M .if the afriction motion resistant is constant at 160N .calculate …
  9. PHYSICS: PLEASE HELP A.S.A.P HMK DUE AT MIDNIGHT T

    During a storm, a car traveling on a level horizontal road comes upon a bridge that has washed out. The driver must get to the other side, so he decides to try leaping the river with his car. The side of the road the car is on is 21.9 …
  10. Physics

    A car accelerates in the +x direction from rest with a constant acceleration of a1 = 1.76 m/s2 for t1 = 20 s. At that point the driver notices a tree limb that has fallen on the road and brakes hard for t2 = 5 s with a constant acceleration …

More Similar Questions