Observe how energy is transferred by light - 4th Grade Science

Light travels in a straight line at an incredible speed of 186,000 miles per second. Light can be affected when it hits an object. Light travels as a wave. It does not need any matter or material to carry its energy along. Light exhibits characteristics of both waves and particles called photons.

Light travels in straight lines as a wave through the air. There is a small portion of the electromagnetic spectrum, which is comprised of visible light that we can see. Televisions, oven display screens, and cell phones all transfer energy through light. They use electricity or chemical energy that is transferred to light energy to generate visible light.

When most people think about light, they think about how electrical currents or chemical energy are used to generate light. Light can make power for people to use in their houses every day. Many people are using solar panels to power their homes, heat their pools, and lower their dependence on electric companies and fossil fuels. Using the Sun's free rays, which do not cause pollution, and are easy to capture, is a great way to generate power for a single home or a whole town.

The leading technology used in home remote controls is infrared (IR) light, which is invisible to the human eye. X-rays are used to take pictures inside the body of bones when looking for breaks or injuries. Ultraviolet light is the type of rays that the Sun puts off, and they can be harmful to your skin and eyes if left unprotected. Visible light is what the human eye can see on the electromagnetic spectrum.

Reflection is the term used to describe light bouncing off of an object. When the light touches an object that is smooth and shiny, it will reflect at the same angle at which it hit the surface of the object. Refraction describes the bending of a light ray when it enters a medium of a different speed. Infrared light refers to a type of light rather than the behavior of light.

The mason jars would better allow light to pass through because they are clear. The sample of fluorite would not allow light to pass through because it is opaque. Opaque objects reemit light waves from the surface back to our eyes rather than allowing it to pass through the object.

This photo is an example of refraction. When light travels from water into the air, it changes direction because it slows down. Keep in mind that refraction is the bending of a light ray when it enters a medium of a different speed. Refraction occurring in water causes the object in the water to appear uneven or as if the portions in and out of the water are different in size.

We can view light with our naked eyes on a spectrum. This spectrum is called visible light. Visible light rays reflect off of the object that you are viewing, so your brain can then process and understand what you are seeing.

White light is colorless, ordinary daylight. It contains all of the wavelengths of visible light at an equal intensity at the same time, which creates beams of white light when focused on a single spot.