Asked in
Science
Geo Prizm
Physics

How can light change direction?

Answer

User Avatar
Wiki User
May 22, 2010 11:18AM

There are various ways to change the direction of light. As a simple example, a mirror changes the direction of light by reflection. When light passes from one medium to another, such as from air to water it changes direction buy a process called refraction. Lenses, camera, telescope, microscope, spectacles, etc. use refraction to change the direction light as it passes from air into glass. A prism bends light is such that the various colors in light are bent different amounts and thus you can see them separately. The atmosphere bends light rays to create rainbows.

A less widely known way light can caused to change direction is by the force of gravity. When light from a star passes close to a massive object in space such as a sun or giant planet or a black hole the gravity of the object pulls on the light changing its direction. This is a primary method of locating black holes -- they exert such tremendous gravitational pull light cannot escape from them (thus they are black and we can't see them), but when light from a star passes near them (but not to near) the bending of the light is a telltale of the black hole.
Lenses, camera, telescope, microscope, spectacles, etc. use refraction to change the direction light as it passes from air into glass. A prism bends light is such that the various colors in light are bent different amounts and thus you can see them separately. The atmosphere bends light rays to create rainbows.

Light changes its direction by bouncing of hard surfaces