The photoelectric effect demonstrates:

$A$ magnet will cause the greatest deflection of

The energies $E_1$ and $E_2$ of two radiations are $25 \ eV$ and $50 \ eV$ respectively. The relation between their wavelengths,i.e.,$\lambda_1$ and $\lambda_2$,will be:

What is the frequency of violet light having wavelength $400 \ nm$?

Explain the visible spectrum and the continuous spectrum.

Which of the following is $NOT$ a property of $X$-rays?