# Bulk modulus

isabella
Anybody knows the formula for bulk modulus? Need answers ASAP

Staff Emeritus
Gold Member
Jelfish said:
If you ever need an equation, it'll probably be faster to look up google or wikipedia than to ask at a message board.
Absolutely true.

However, in just this one case, Wiki has a small error in the equation they provide. That equation is missing a minus sign. It should read :

$$K= -V~ \frac { \Delta P}{\Delta V}$$

where

$$\Delta P \equiv P_{final} - P_{initial}$$

$$\Delta V \equiv V_{final} - V_{initial}$$

Still, this has taken half a day, for something that can be found in less than 5 minutes using Google. But this way, you have to do no work.

Last edited:
The sign error has been corrected.