# Coulombs constant

1. Apr 13, 2010

### turkusmaximus

I have equation that i have to make A the subject of so the equation is F = A Q1 Q2/r2 this i have done and it becomes A = F x r2/Q1 Q2. the SI units work out as coulombs constant, however on all the web sites i have checked coulombs constant is given as K, even the equations are identical except in all of them the A is a K. Is this a British thing or can A be used instead of the K?

2. Apr 13, 2010

### Staff: Mentor

The letter used to represent a quantity is not important. You can use any letter you like. For example, if you wanted to you could write Newton's 2nd law as:

a=bc
where a is the net force, b is the mass, and c is the acceleration.

You would confuse everyone reading it, but it would be a perfectly legitimate equation.

3. Apr 13, 2010

### turkusmaximus

I appreciate that and thank you for it but just to make that observation more clear to me do you know of an example where coulombs constant has been called A. One website had something down like s-A for it but it does not mean anything to me at this time?

4. Apr 13, 2010

### Ali Inam

You can use any form that is suitable for you. No matter it is K (which I have seen almost everywhere) or A(which I have seen only once)

The important thing is that you must elaborate any form which you are using.

You must mention that what exactly is K or A ?

This will do the trick for you