Physics

posted by .

If you step on your car's brakes hard, the wheels stop turning (i.e., the wheels "lock") after 1.5 revolutions.

At the same constant acceleration, how many revolutions do the wheels make before stopping if your initial speed is twice as high?

  • Physics -

    wf^2=wi^2+2A*displacement

    A= -wi^2/2(1.5rev)

    if initial speed is the doubled, then w^2 term in the numerator is x4, so rev must be x4 to keep A constant.

    so 4x1.5=6rev

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. College Physics

    A cyclist starts from rest and pedals so that the wheels make 7.7 revolutions in the first 5.1 s. What is the angular acceleration of the wheels (assumed constant)?
  2. physic

    Hi!Need help please. Question:A car initially traveling at 24.0 m/s undergoes a constant negative acceleration of magnitude 2.10 m/s2 after its brakes are applied. (a) How many revolutions does each tire make before the car comes to …
  3. Physics

    A car initially traveling at 33.4 m/s undergoes a constant negative acceleration of magnitude 1.80 m/s2 after its brakes are applied. (a) How many revolutions does each tire make before the car comes to a stop, assuming the car does …
  4. Physics

    A car initially traveling at 33.4 m/s undergoes a constant negative acceleration of magnitude 1.80 m/s2 after its brakes are applied. (a) How many revolutions does each tire make before the car comes to a stop, assuming the car does …
  5. Physics

    A cyclist starts from rest and pedals so that the wheels make 7.7 revolutions in the first 5.1 s. What is the angular acceleration of the wheels (assumed constant)?
  6. physics

    A car initially traveling at 31.0 m/s undergoes a constant negative acceleration of magnitude 2.00 m/s2 after its brakes are applied. (a) How many revolutions does each tire make before the car comes to a stop, assuming the car does …
  7. phys6

    A cyclist starts from rest and pedals so that the wheels make 8.1 revolutions in the first 5.4 s. What is the angular acceleration of the wheels (assumed constant)?
  8. Physics

    A car travels at 64 mi/h when the brakes are suddenly applied. Consider how the tires of a moving car come in contact with the road. When the car goes into a skid (with wheels locked up), the rubber of the tire is moving with respect …
  9. Math

    A truck with 40-in.-diameter wheels is traveling at 50 mi/h. a) Find the angular speed of the wheels in rad/min b) How many revolutions per minute do the wheels make?
  10. Trigonometry

    a bicycle with 24inch diameter wheels is traveling at 15mi/hr. a) Find the angular speed of the wheels in rad/min. b)How many revolutions per minute do the wheels make?

More Similar Questions