If two monochromatic light waves undergo destructive interference, the amplitude of the resultant wave is

The amplitude is 0. (assuming that the amplitude ot both initial waves is the same)

Explanation:

When two monochromatic light waves of the same wavelength and same amplitude undergo destructive interference, means that the peak of one of the waves coincides with the trough of the other, so the waves "cancel" each other in that point in space.

Then if two light waves undergo destructive interference, the amplitude of the resultant wave in that particular point is 0.

beta is electron from nucleus

something from nucleus has changed, but charge must be same for cons of charge