# Physics

A race car can be slowed with a constant acceleration of -11 m/s^2

a. If the car is going 55 m/s, how many meters will it travel before it stops?

b. How many meters will it take to stop a car going twice as fast?

According to one of the teachers this is what they stated

A. stopping distance = (stopping time) x (average speed)
= (V/a)*(V/2) = V^2/(2a)

B. If the speed doubles, with deceleration rate "a" staying the same, the stopping distance is four times farther.

Ok, to find the distance for the first one i understand. I'm pretty sure this is how you do it

d = Vit
d = 55 x 5
d = 275 m

But for b, Would i have to double the speed for this which is 55 x 2 = 110 and would i also have to increase the stoppping distance which is 275 m by multiplying by 4

1. 👍
2. 👎
3. 👁

Yes, the stopping distance quadruples if you double the speed.

Stopping distance = V^2/(2a)
that you don't understand?

1. 👍
2. 👎
2. Ok, i just understand this a little. I know it has been answered twice by you and i thank you for that. Can you tell me if this right below?

a. stoppping distance = v^2 / 2a
sd = 55^2 / 2(- 11)
sd = 3025 / - 22
sd = -137.5 m

b. Therefore, if the stopping distance quadruples then i shouldn't put that in the equation of:

sd = v^2 / 2a
sd = 110^2 / 2 (- 11)
sd = 12100 / -22
sd = -550 m

Is this right? Thanks i appreciate this a lot and happy new yr.

1. 👍
2. 👎

## Similar Questions

1. ### physics

A locomotive is pulling an empty freight car with a constant acceleration on a horizontal surface. The mass of the locomotive is five times the mass of the car. Which statement is true about the force applied by the car on the

2. ### Physics

A race driver has made a pit stop to refuel. After refueling, he leaves the pit area with an acceleration whose magnitude is 6.0m/s 2 . After 4.0s he enters the main speedway. At the same instant, another car on the speedway and

3. ### physics

A race car moving with a constant speed of 60 m/s completes one lap around a circular track in 50 s. What is the magnitude of the acceleration of the race car?

4. ### 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

1. ### PHY SCI

A race car goes around a circular, level track with a diameter of 1.00 km at a constant speed of 90.0 km/h. What is the car's centripetal acceleration in m/s^2?

2. ### English

Which sentence describes a race car using onomatopoeia? A. The sweet car went around the track quickly. B. The rapid race car drove around the track. C. The fast car traveled around the roadway D. The sleek, powerful race car

3. ### physics

Cars A and B are racing each other along a straight path in following manner: Car A has head start and is a distance dA beyond starting line at t=0. The starting line is at x=o. Car A travels at constant speed vA. Car B starts at

4. ### physics

Last question from me Suppose the driver in this example is now moving with speed 39.6 m/s, and slams on the brakes, stopping the car in 4.1 s. (a) Find the acceleration assuming the acceleration is constant. m/s2 (b) Find the

1. ### 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

2. ### 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

3. ### physics

Two cars are traveling at the same constant speed v. Car A is moving along a straight section of the road, while B is rounding a circular turn. Which statement is true about the acceleration of the cars? a.) acceleration of both

4. ### physics

The combined mass of a race car and its driver is 600. kilograms. Traveling at a constant speed, the car completes one lap around a circular track of radius 160 meters in 36 seconds. A) Based on the given information, calculate