i think there is no violation................ as red has maximum wavelength, it has least energy.............as e in inversely proportional to wavelength......... also, violet has a more energy wen compare to red.............since its wavelength is less than that of red ................so, wen red light is passed through violet paper, energy is ditributed from violet to red and wavength of red decreases due to this,,,,,,, as wavenght decreases, colour will change into violet, as violet is the loser of energy...also wavelength decreases.......