Write the formula for velocity of EM waves in vacuum and in given medium?

Write the formula for intensity of a wave in EM waves.

Calculate the velocity of EM waves in vaccum.

What is velocity of the wave ?

Define the following: Velocity of wave

What is velocity of sound wave ?

State the formula for the velocity of transverse waves on stretched wire and obtain an expression for fundamental frequency of vibration of stretched string.

What are EM waves?

For sound waves, the Doppler formula for frequency shift differs slightly between the two situations: (i) source at rest observer moving, and (ii)source moving observer at rest.The exact Doppler formulas for the case of light waves in vacuum are, however,strictly identical for these situations.Explain why this should be so.Would you expect the formulas to be strictly identical for the two situations in case of light travelling in a medium?

At nodes, the velocity of stationary wave is