The Motion of Light in Water

Light travels through water at a slower speed than in air because water is denser, causing the light waves to bend and slow down due to refraction. When light enters water from air, it changes direction at the boundary, which explains why a straw looks bent in a glass of water. This bending occurs because light moves at different speeds in different media, following the principle of refraction. The change in speed and direction depends on the water’s density and the light’s angle, illustrating how water affects the path and properties of light passing through it.