Description: After studying this lesson, you should be able to learn about, propagation of transverse and longitudinal waves and establish the relation v = vλ, Newton’s formula for velocity of longitudinal waves in a gas and explain Laplace’s correction, the factors on which velocity of longitudional waves in a gas depends, formation of transverse waves on stretched strings, the equation of a simple harmonic wave, the phenomena of beats, interference and phase change of waves on the basis of principle of superposition, formation of stationary waves and discuss harmonics of organ pipes and stretched strings, Doppler effect and apply it to mechanical and optical systems, the properties of em waves, wavelength range of different parts of em spectrum and their applications