5.2 Intensity $(I)$

2.1 Transverse waves
2.2 Longitudinal waves
2.3 Differences between transverse and longitudinal waves

3.1 General equation of wave motion
3.2 Wave function
3.3 Equation of a plane progressive harmonic wave
3.4 Important relations

4.1 Speed of different types of wave

5.1 Power $(P)$
5.2 Intensity $(I)$

It is defined as the amount of energy flow per unit area per unit time in a direction perpendicular to the propagation of wave. It is denoted by the symbol $I$. It is given as, $$\begin{equation} \begin{aligned} {\text{Intensity}}\;{\text{ = }}\frac{{{\text{Power}}}}{{{\text{area of cross - section}}}} \\ I = \frac{{\frac{1}{2}\rho {\omega ^2}{A^2}sv}}{s} \\ I = \frac{1}{2}\rho {\omega ^2}{A^2}v \\\end{aligned} \end{equation} $$