Physics Homepage

Useful Math Skills

Solving Equations

We will be using very simple math throughout the year. This will mostly be arithmetic, diving and multiplying numbers. We will also solve  a few very simple equations, like  or.  Without concerning ourselves with the meaning of the symbols, we should be able to solve these equations for a variable other than F or v.

Solve F= ma for a:


  • m and a are connected by multiplication
  • Therefore we need to divide both sides by m in order to eliminate m on the right side.


  • the m’s cancel out on the right side


  • note, that I left the a on the right side
  • sometimes it is easier to leave the variable you are looking for on the right side and flip the equation at the end.

Please not that every time I change the equation I use a new line and all of the equal signs are lined up

You could also have. flipped the equation around in the beginning.
Math 3

Often you will want to write this:

MATH 4 .

Here all the operations are written into one line and although I can guess as to what you are trying to do, it doesn’t make much sense and in most cases will be wrong.


  • delta t is in the denominator and is connected to d by division



  • Therefore we need to multiply both sides by delta t in order to eliminate delta t on the right side.


  • the delta t’s cancel out on the right side





here is a simple trick that might help you solve these equations. Write the equation, for instance , into a triangle. You will see how the equation shows up inside this triangle by looking at the two ovals.





You will see how the equation shows up inside this triangle by looking at the two ovals.




If you want to solve for d = vDt, the triangle read like this:  



Solving for Dt which will lead math can also be accomplished with his triangle as you can see on the left.



This might all seem too easy to worry about, but when we are solving problems in class on tests or on the exam, not being able to solve such equations is the source for most of the errors I will have to correct.

Click here to learn more about scientific notation.


Website maintained by Volker Krasemann.