## College Physics (4th Edition)

$P_1+\frac{1}{2}\rho~v_1^2+\rho~g~h_1 = P_2+\frac{1}{2}\rho~v_2^2+\rho~g~h_2$ We can think of each term in Bernoulli's equation as an energy density. $P_1$ is the pressure energy density, $\frac{1}{2}\rho~v_1^2$ is the kinetic energy density, and $\rho~g~h_1$ is the potential energy density. The form of the equation shows that the energy density is conserved. Bernoulli's equation is an expression of conservation of energy. The correct answer is: (b) conservation of energy