The bulk modulus of water is roughly $2.2 imes 10^9 ext{ Pa}$, while that of air at normal condit

Question

The bulk modulus of water is roughly $2.2 	imes 10^9	ext{ Pa}$, while that of air at normal conditions is roughly $1.0 	imes 10^5	ext{ Pa}$. What fundamentally explains why the bulk modulus of water is significantly larger than that of air?

Professor PC Thomas Classes · Answer

Bulk modulus measures resistance to compression. In liquids like water, molecules are already packed closely. Compressing them further acts against very strong short-range intermolecular repulsive forces, requiring high pressure for a small volume change.