Finding Velocity from a Data Table
Physics
Finding Velocity
In this video, we are going to learn how to find the average velocity between two times given a data table. We're going to use this example data right over here. We have time in seconds in the left hand column and position in meters in the right hand column. So if you recall, we have a velocity formula that says your average velocity is equal to your change in position. Divided by your time interval. Now when you're asked to find average velocity between two times in a data table, you will usually be given which two times to use for your time interval. So what we're going to do is we're going to use the times of two seconds and four seconds and our problem is going to be what is the average velocity between the time of two seconds and four seconds.
So what we need to do then is we need to figure out what is the change in position that is final position minus initial position. And what is the time interval over which this change in position occurred? So this is going to be final time minus initial time. And if you notice from our data table, this is our initial time at two seconds. This is our final time at four seconds, which would make this our initial position. And this our final position. So all we have to do is plug these numbers into our formula up here. So we're going to say the velocity is equal to our final position, which was 5.6 meters. Minus our initial position three .0 meters, divided by our final time, which was four seconds, minus our initial time, which was two seconds.
This is going to give us 2.6 meters over two seconds. We plug that into our calculator, we will find that our velocity is going to be 1.3 meters per second. And that's how you find velocity from a data table. You're going to be given an initial and a final time, and you just use the positions that go along with that. Remember you're changing position is final position minus initial, and your time interval is just final time, minus initial time.