1.State Newton's formula for speed of sound in air and explain Laplace's correction $v = \sqrt{\frac{\gamma P}{\rho}}$.
2.State Principle of Superposition of Waves and define stationary (standing) waves.
3.Derive the fundamental frequency and harmonics of an organ pipe open at both ends ($f_n = n \frac{v}{2L}$).
4.What are Beats? Derive beat frequency formula $f_{beat} = |f_1 - f_2|$.
