Question

Coherent source have -

• A. same frequency
• B. same wavelength
• C. constant phase difference
• D. All of these

Answer 1

The correct option is D All of these

Coherent source of light are those sources which emit a light wave having the same frequency, wavelength and in the same phase, or they have a constant phase difference.

Hence, option $\left(D\right)$ is the correct answer.