# Find the angle that the total acceleration of the car makes

1. Feb 11, 2004

### Maxwell

Ok, this is a type of question I have seen on a quiz, and in my homeworks. I have gotten it wrong both times.

This problem seems to be reoccuring, and I am pretty sure it will be on my test on friday.

This is the question:

"A race car starts from rest on a circular track. The car increases its speed at a constant rate a(sub i) as it goes once around the track. Find the angle that the total acceleration of the car makes - with the radius connecting the center of the track and the car - at the moment the car completes the circle."

Now I understand some aspects of the question, like this is a Tangential and Radial acceleration problem. But what I am looking for is a sort of guide through these types of problems, so I can tackle any problem that is like this.

Also, the question on my quiz was this, but it asked different types of questions about the circle. I will get it back tomorrow and post the variation.

Thank you very much.

2. Feb 12, 2004

### Staff: Mentor

To find the radial component of the acceleration, you need the speed. Find the speed however you can. $a_r=\frac{v^2}{r}$

The tangential acceleration $a_t$ is given. Find the total acceleration by adding the two vector components. (The angle can be found by drawing the triangle representing the vector addition. And a little trig.)

3. Feb 12, 2004

### turin

Two things:
1) Do all of the HW problems in your book (and I'm only slightly joking).
2) Draw a picture.