Distance using acceleration and time

[mattykay]

Homework Statement

A car accelerates from 15 m/s to 28 m/s in 6.4 s. How far did it travel in this time?

Homework Equations

Unsure- have tried several, and all results have been wrong
Part 1 was to determine acceleration, which is 2 m/(s^2)

The Attempt at a Solution

I've come up with 44, 41, 19, and 83 meters, all of which have been wrong.

 

[Doc Al]

Part 1 was to determine acceleration, which is 2 m/(s^2)

Seems OK

The Attempt at a Solution

I've come up with 44, 41, 19, and 83 meters, all of which have been wrong.

Show what you've done.

There are several ways to solve this. One way is to use the average speed.

 

[rock.freak667]

Do you know your kinematic equations?

Alternatively, if you plot a v-t graph, do you know how to obtain the distance traveled from that graph?

 

[mattykay]

I got it; I was using one formula, when I should have been using d=((vf+vi)/2)*t

 

[rock.freak667]

Using d=ut + 1/2 at² should have given the same answer.