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 of a2 = -5.93 m/s2.

Write an expression for the car's speed just before the driver begins braking, v1.

If the limb is on the road at a distance of 550 meters from where the car began its initial acceleration, will the car hit the limb?

  1. 👍
  2. 👎
  3. 👁
  1. V1 = a1*t1 = 1.76 * 20 = 35.2 m/s.
    d1 = 0.5a1*t1^2 = 0.88*20^2 =

    V2 = V1 + a*t = 35.2 - 5.93*5 = 5.55 m/s. The 5-second deceleration is not enough to bring the car to a full stop.

    d2 = V1*t + 0.5a*t^2.
    d2 = 35.2*5 - 0.5*5.93*5^2 =

    d = d1+d2 =

    1. 👍
    2. 👎

Respond to this Question

First Name

Your Response

Similar Questions

  1. Physics

    Suppose that a car traveling to the West (-x direction) begins to slow down as it approaches a traffic light. make a statement concerning its acceleration. a) the car is decelerating and its acceleration is positive b)the car is

  2. physics

    4. A 1500 kg car starts from rest and drives around a flat 50 m diameter circular track. The forward force provided by the car’s wheels is a constant 1000 N. a. What are the magnitudes and direction of the car’s acceleration

  3. Physics

    Two cars start from rest at a red stop light. When the light turns green, both cars accelerate forward. The blue car accelerates uniformly at a rate of 3.6 m/s2 for 4.5 seconds. It then continues at a constant speed for 7.3

  4. physics

    A rocket, initially at rest on the ground, accelerates straight upward from rest with constant acceleration 29.4 . The acceleration period lasts for time 9.00 until the fuel is exhausted. After that, the rocket is in free fall.

  1. physics

    A car, starting from rest, accelerates in the +x direction as in the figure. It has a mass of 1.10 × 103 kg and maintains an acceleration of +4.40 m/s2 for 2.60 s. Assume that a single horizontal force (not shown) accelerates the

  2. physics

    Two cars cover the same distance in a straight line. Car A covers the distance at a constant velocity. Car B starts from rest and maintains a constant acceleration. Both cars cover a distance of 487 m in 216 s. Assume that they

  3. Physics

    A car, starting from rest, accelerates in the positive x direction. It has a mass of 1.10 x 103 kg and maintains an acceleration of 4.6 m/s^2 for 5 s. Assume that a single horizontal force accelerates the vehicle. Determine the

  4. AP ECE Physics

    A car at the Indianapolis-500 accelerates uniformly from the pit area, going from rest to 295 km/h in a semicircular arc with a radius of 190 m. Determine the tangential acceleration of the car when it is halfway through the turn,

  1. physics

    A car is traveling at a constant speed of 27.1 m/s on a highway. At the instant this car passes an entrance ramp, a second car enters the highway from the ramp. The second car starts from rest and has a constant acceleration. What

  2. physics

    A car sits in an entrance ramp to a freeway, waiting for a break in the traffic. The driver sees a small gap between a van and an 18-wheel truck and accelerates with constant acceleration along the ramp and onto the freeway. The

  3. physics

    Vroom-vroom! As soon as a traffic light turns green, a car speeds up from rest to 50.0 mi/h with a constant acceleration of 8.40 mi/h·s. In the adjoining bike lane, a cyclist speeds up from rest to 20.0 mi/h with a constant

  4. physics

    Q: Two cars start from rest at a red stop light. When the light turns green, both cars accelerate forward. The blue car accelerates uniformly at a rate of 5.7 m/s2 for 3.2 seconds. It then continues at a constant speed for 8.8

You can view more similar questions or ask a new question.