Changing Equations Don and Nick

Changing Equations  We will show you how to change equations so that you can solve for different variables.  For example, if you’re using the equation x=v 0 t+1/2at 2 you will learn to change it to a=2(x-v 0 t)/t 2 so that you can solve for acceleration.  We will show you how to change equations so that you can solve for different variables.  For example, if you’re using the equation x=v 0 t+1/2at 2 you will learn to change it to a=2(x-v 0 t)/t 2 so that you can solve for acceleration.

Changing Equations  First you’ll need to find which equation is the correct one to use. For now we’ll use x=1/2(v+v 0 )t  Then you need to find which variable you are solving for. We’ll same that we know v, x and t and are solving for v 0  First you’ll need to find which equation is the correct one to use. For now we’ll use x=1/2(v+v 0 )t  Then you need to find which variable you are solving for. We’ll same that we know v, x and t and are solving for v 0

Changing Equations  Start with your equation x=1/2(v+v 0 )t  First multiply by two on both sides to get rid of 1/2  2x=(v+v 0 )t Now divide by t on both sides  2x/t=v+v 0 Finally subtract v so that v 0 is by itself.  2x/t-v=v 0  Start with your equation x=1/2(v+v 0 )t  First multiply by two on both sides to get rid of 1/2  2x=(v+v 0 )t Now divide by t on both sides  2x/t=v+v 0 Finally subtract v so that v 0 is by itself.  2x/t-v=v 0

Changing Equations  Now try these for practice  v=v 0 +at in terms of a  x=v 0 t+1/2at 2 in terms of v 0  v 2 =v ax in terms of x  Now try these for practice  v=v 0 +at in terms of a  x=v 0 t+1/2at 2 in terms of v 0  v 2 =v ax in terms of x

Changing Equations  Answers  (v-v 0 )/t=a  (x-1/2at 2 )/t=v 0  (v 2 -v 0 2 )/2a=x  Answers  (v-v 0 )/t=a  (x-1/2at 2 )/t=v 0  (v 2 -v 0 2 )/2a=x