# how do i determine an objects velocity by looking at a acceleration vs time graph?

how do i determine an objects velocity at certain times by looking at a acceleration vs time graph

http://session.masteringphysics.com/problemAsset/1...

heres the graph and i need to know wat the velocity at times 2s,4s,6s,and 8s .... i cant seem to come up with the right answers

im getting 0,5,20,-30,0 and its telling me its wrong

### 3 Answers

- 1 decade agoFavourite answer
Acceleration is distance per unit time per unit time.

When you multiply that by time you get distance per unit time. That's velocity.

So the answer is find the area of the graph at that instant. Get the graph, and at the instant you want to find the velocity draw a vertical line. Then find the area of the shape the graph makes to the left. For example, if when you draw the line you make a rectangle, just multiply the x-value by the y-value. If it makes a triangle, then x*y/2. But odds are it won't, and you'll get an odd shape.

- loukxLv 44 years ago
??? what percentage dots are there? The should be gradually increasing in separation. you pick a minimum of three dots to get 2 velocities, the version interior both velocities divided by the time enormous difference between midpoints between the dots stands proud because the acceleration. the better the separation between both instruments of dots used to derive the velocities, the more advantageous precise the estimate of acceleration. So, you want to calculate 2 velocities.

- 1 decade ago
pick a time

find its corresponding acceleration

divide the acceleration by the time