Comparing the masses of the two photons, of red light and violet light

Red and violet light have

The wavelengths of violet and red ends of visible spectrum are 390nm and 780 nm respectively. Evaluate the energy range of the photons of the visible light in electron volts.

How does focal length of a lens change when red light is replaced by violet light?

A near ultra violet photon of wavelength 300nm is absorbed by a gas and then emitted as two photons. One photons is of red light with wavelength 760nm . What would be the wave length of the second photon?

A near ultra violet photon of wavelength 300nm is absorbed by a gas and then emitted as two photons. One photons is of red light with wavelength 760nm . What would be the wave length of the second photon?

A near ultra violet photon of wavelength 300nm is absorbed by a gas and then emitted as two photons. One photons is of red light with wavelength 760nm . What would be the wave length of the second photon?

(a) Compare the speed of light of wavelength 4000 Å (i.e., violet light) and 8000 Å (i.e. red light) in vacuum. (b) How is the refractive index of a medium related to the speed of light in it and in vacuum or air ?

The energy of a photon of red light (8000 A^@) is nearly