# Getting confused on how to determine which equation to use?

1. Jan 16, 2014

### emlekarc

So we are talking about velocity and acceleration, as well as the Kinetic Motion equations. Everyone is saying to make a chart, if you will, seeing which variables are present and which one you need. They say this will help you in picking an equation. However, I am still really having a hard time in picking the variables out of a problem...Does anyone have any tips or maybe a sample problem that you could pick the variable out of so I could see a sample?

Thank you so much!

2. Jan 16, 2014

### Staff: Mentor

I think you need to get a feel for it. You can do this best, in my opinion, by working lots of problems. Nothing beats experience and practice.

Chet

3. Jan 16, 2014

Its so easy,for example,:
A car initially traveling with a velocity of 100m/s comes to rest in 30s.
What is the distance travelled during this time?

The variables here are initial velocity,final velocity and time so you can use $S=\frac{1}{2}(u+v)t$
Try to write all the equations and find the one with all the variable in question.