# Importance of constants

1. Aug 3, 2006

### mphr

why should there is a 'constant' in a formula in which charactors on both sides are propotional to each other? and what should be the importance of it?

Last edited: Aug 3, 2006
2. Aug 3, 2006

### neutrino

Two quantities are said to be proportional when their ratio is a constant. If some variable y is proportional to another variable x, then their ratio, y/x, is a contant.

y/x = k => y = kx. (k is some constant)

3. Aug 3, 2006

im not sure that i understood ur question...
are u asking what role constants play in pysical equations?

because is u do, my answer is that those constants are there to keep all physical equations in the same unit system...

lets take the niotonic equation on the gravitational force:
F=GMm/r^2
this equation in principle is the same as : F=Mm/r^2.

though such formation of the equation, will not give us the force in newtonic units, so we cannot compare this force to other known foces other than gravity...

i hope i was clear though my crippled skills in english...

4. Aug 3, 2006

### rbj

you can define units that get rid of these constants of proportionality. these are often called "natural units". check out:

http://en.wikipedia.org/wiki/Natural_units

and take your pick of which constants to lose.

5. Aug 3, 2006