How to find the frequency of the wave

The frequency of the waves is one of her most important physical characteristics. The frequency of a wave is the number of complete vibrations or cycles the wavecommitted per unit of time. If the time unit is second, the frequency of the wave measured in Hertz (Hz).

You will need

• wavelength, wave number, phase velocity, energy of a particle

Instruction

1. Let L be the length of the wave, V is its phase velocity, and T the period of oscillation of a wave. Then, by definition, L = VT = V/f, where f is the frequency of the wave. Thus through the length of the wave and its phase velocity is frequency of a wave is expressed by the formula: f = V/L.
2. Using these values we can Express the circular frequency of the wave w. By definition, the circular frequency is expressed via the frequency f by the formula w = 2*pi*f. Then w = 2*pi*V/L.
3. You can find the frequency, knowing the wave number k = 2pi/L, the inverse length of the wave. Substituting expressed through this formula the L value into the formula for frequency of a wave, we get: f = k*V/(2pi). Accordingly, w = k*V.
4. From quantum theory it is known that the frequency of any electromagnetic radiation is proportional to the energy of its constituent photons. Waves associated with the microparticle and displaying the quantum nature of called, the de Broglie waves. The frequency of the wave de Broglie wave is related to its energy through Planck's constant: f = E/h, where h is Planck's constant.