The scattering of light by particles in its path is called Tyndall effect. When a beam of light enters a smoke-filled dark room through a small hole, then its path becomes visible to us. The tiny dust particles present in the air of room scatter the beam of light all around the room. Thus, a scattering of light makes the particles visible. Tyndall effect can also be observed when sunlight passes through a canopy) of a cleanse forest. Here, tiny water droplets in the mist scatter light.