# Constant Acceleration Car

1. Jan 13, 2008

### ae4jm

[SOLVED] Constant Acceleration

1. The problem statement, all variables and given/known data
a. What constant acceleration, in SI units, must a car have to go from zero to 60 mph in 10s?

b. What fraction of g is this?

c. How far has the car traveled when it reaches 60 mph? Give your answer both in SI units and in feet.

2. Relevant equations

3. The attempt at a solution
I have gotten answers for parts a and b, but I get really confused on part c.

For a: 1 mph = .447 m/s, so 60(.447)=26.82 m/s. (26.82 m/s)/(10s)=2.68 m/s^2

For b: g=gravity=9.8 m/s^2. (2.68 m/s^2)/(9.8 m/s^2)=.273(100)=27.3%

For c: I'm not sure where to start to find my answer.

I appreciate any help!

I just solved it! I've worked on part C for about 45 minutes to an hour. I just found an equation that worked, imagine that.

For c: I used d=Vi(t)+0.5(a)(t^2) So, d=(0 m/s)(10 s)+0.5(2.68 m/s^2)(10^2)=134 m. Then to convert 134 m to feet = 134(39.37)=5,275.58 in/12=440 ft

Hopefully this will help someone else out that is new to physics, like myself.

Last edited: Jan 13, 2008
2. Jan 13, 2008

### olgranpappy

use one of them there equations from your textbook:
$$x = \frac{1}{2}a t^2 + v_0 t + x_0$$

3. Jan 13, 2008

### ae4jm

This is the exact equation I used! Please see the bottom of my previous post, I just finished editing my initial post. I appreciate your help, all of the great help I've received from this forum!

4. Jan 13, 2008

### olgranpappy

ah. well, that's good.

5. Jan 14, 2008

### white 2.5rs

Yeah and hopefully your teacher can help... oh wait....