light+energy

There are five properties of light. Here are some of them: intensity, frequency or wavelength and phase Light, which exists in tiny "packets" called photons, exhibits properties of both waves and particles. This property is referred to as the wave-particle duality. The study of light, known as optics, is an important research area in modern physics. Did you know Thomas Edison light bulb inventor was afraid of the dark that is why Thomas built the light bulb. Sound can travel in air, wood, steel, and water, but it cannot travel in space. So when you hear those explosions of star ships in star trek, you now know that in real life you wouldn't hear anything. Light however, can travel in a vacuum (absence of any matter). We know this because we can see light in space, and space is a vacuum. Light not only acts as a wave, but it sometimes acts as a stream of particles. It has a dual nature. Characteristics of particles include that light travels in straight lines and in a beam. In the modern theory of light, we think of light to be a series of packets of energy. These packets have no mass and carry quantified amounts of energy.Light plays a very important role in our lives. Without light we would not be able to see. Light from the sun generates heat, and can be used to generate electricity. To do this, light must travel to us. Do you know what light is, and how light travels to us? Light, whether from the sun or some object, travels in a straight line. This can be easily seen by shining a flashlight in the dark. Light rays can bounce off materials, like walls, to provide light to other areas like around corners. Light is a form of energy. If you hold your hand near a light you will feel it get hot. Some light sources can get so hot that they can burn you. Some objects, like windows, are transparent allowing light to pass through them. Other objects are opaque, blocking the light from going through them. Some surfaces, like a mirror, cause the light to bounce off. The light bounces off, or reflects back, at the same angle that it hit the surface. The amount of light reflected depends on the type of surface. Shiny surfaces reflect lots of light. Dull surfaces reflect very little light. When you look in a mirror, you see yourself because the light shining on your body is reflected from the mirror back to your eyes. When a light ray travels through a material the direction of the light will change. This is called refraction. The amount the light bends depends on the type of material. A lense can cause light to change direction. If you have ever used a magnifying class to focus light to a small point, you are seeing refraction at work.
 * Light** is electromagnetic radiation of a wavelength that is visible to the human eye. In physics, the term //light// sometimes refers to electromagnetic radiation of any wavelength, whether visible or not.