We know very well the "light" because that light is always around us, the light is badly needed by the creatures that exist in this world either human or other animals, although some animals live in darkness.
Experts say that light is one form of energy that many benefits. Light can come from the sun, lights, flashlights, or lain.Benda-objects that can produce light is called a source of light. The main source of light for the earth is the sun that shines the entire universe this highway.
According to the British physicist james clark maxwel (1831-1879), light is the wave propagation produced by the combined electric field and magnetic field. Waves generated from a combination of electric fields and mmedan magnets are called electromagnetic waves.
Then light can be divided into two, visible light and invisible light. Visible light is a white light that our eyes can perceive. non-visible light such as x-rays, ultraviolet rays, gamma rays, and infrared rays and other rays are considered hidden.
1. Light that extends straight
Light that is considered a straight vine is like the light of a car or motorcycle light at night? how does the light propagate? It looks straight, does not it? Similarly, if you turn on the flashlight and direct it to the wall, it will become more obvious that the light is propagating straight. Have we ever noticed.
2. To penetrate a clear object
Whereas the light that can penetrate a clear object is like, flash the light to the carton perfectly. Objects that can carry the light perfectly are called transparent objects. Examples of clear objects include clear water and clear glass and hard objects such as transparent stones.
Then on geals containing soapy water, only a portion of the light is passed on. The light captured by the cardboard looks dim. Objects that can continue light but are not perfect, are called cloudy objects. Examples of cloudy objects include soapy water and tea water and other cloudy waters that are thought to penetrate the above mentioned light.