# Two dimensional acceleration question

1. Sep 19, 2005

### F.B

My book stinks it doesnt explain or show you how to do enough examples. But anyways i have another problem now. I figured out how to do my other question. Anyways my question is.......

A car with a velocity of 25 m/s [E] changes its velocity to 25 m/s in 15s. Calculate the car's average acceleration.

How do i start this question off. I dont know what to do.

2. Sep 19, 2005

### 2Pac

Are we looking for a magnitude of acceleration or a vector form?

3. Sep 19, 2005

### F.B

the magnitude and degrees/direction

4. Sep 19, 2005

### Staff: Mentor

Use the definition of average (vector) acceleration:
$$\vec{a}_{ave} = \frac{\Delta \vec{v}}{\Delta t}$$

(Hint: To find the change in the velocity, write the initial and final velocity in component form and then subtract.)