I have studied about the dual nature of light and all the experiments that proved light was a wave and sometimes a particle, and I am comfortable with the concept that it can be both. However, I have a few questions I am confused about.
1) If I have two different colours of light, I know that they are waves with different frequencies if I look at their wave nature, but what causes colour difference according to particle nature? Is it number of photons or energy that the photon contains?
2) according to wave nature, energy is proportional to amplitude of a wave. Does it mean a red beam of light can have more energy than another one if I increase its amplitude? And how do I increase its amplitude? (By shining more light?)
3) what exactly does amplitude and frequency correspond to in particle nature and wave nature and how do I physically see it (color, brightness, etc) If some one could explain using analogies, that would be great.