Curiosities
Tap a card to reveal it.
A prism does not create colours.
It only separates colours already present in white light.
Violet bends the most.
Shortest wavelength → highest refractive index → largest deviation.
Red bends the least.
Longest visible wavelength means smallest refractive index and deviation.
Visible light is a tiny slice.
It covers only 400–700 nm of an EM spectrum spanning many decades.
UV can sterilise.
Short-wavelength UV damages microbial DNA — used in hospitals and water plants.
Your TV remote uses IR.
Near-infrared LED pulses carry the button code to the TV's IR receiver.
Astronauts see a black sky.
Without atmosphere there's no scattering, so the sky away from the sun is dark.
Clouds are white.
Large water droplets scatter all colours equally, mixing back to white.
Red light travels farther in fog.
Long λ ⇒ small Rayleigh scattering ⇒ better visibility through haze.