If a light beam hits a mirror, it reflects back at a different angle. The angle at which the beam hits the mirror is called the angle of incidence, and the angle at which it reflects is called the angle of reflection. These two are always equal.
Prisms can also bend light, and at the right angle, can separate white light into its primary colors which are red, orange, yellow, green, blue, indigo, and violet. Each color is bent at a different angle in the prism, which is why they are always in that order.
 |
| A prism separating light into its primary colors. Photo courtesy of: www.ask.com |
When a beam of light goes through glass or a container that is curved and then leaves it, the bent light rays cross. The point where they cross is called the focal point, and the distance between the focal point and the glass or container is called the focal distance. This is also how glasses work; if you are nearsighted or farsighted, the focal point will not be on your retina, but the glasses will bend the light so the focal point will be on your retina.
Refraction is when light enters another substance, such as water, after moving through air. The water bends the light and the light slows down ever so slightly. Once the light leaves the water it bends again and this is why things partly in water look bent, and things under water aren't where they appear to be
.
No comments:
Post a Comment