Summary
Highlights
Refraction occurs when light bends as it travels from one medium to another. This happens because the speed of light changes, causing objects to appear distorted. An example is a popsicle stick appearing bent in a glass of water due to the change in light's speed as it moves from air to water.
Light is the movement of energy through space, traveling as electromagnetic radiation composed of electric and magnetic fields. It can travel through mediums like air or water, or even a vacuum. The electromagnetic spectrum classifies light waves by their size.
When light rays encounter an object, they can be transmitted (pass through), absorbed, reflected (bounce back), or refracted (bend). The specific interaction depends on the light wave's energy and the arrangement of molecules in the material, which also gives objects their color.
Reflection is when a light wave bounces off a surface. The law of reflection states that the angle at which light hits a surface is the same as the angle at which it bounces off. This phenomenon allows us to see ourselves in mirrors and perceive the color of objects that don't produce their own light, as they reflect specific colors.
Absorption is the transfer of energy from a light wave to the matter it passes through. For example, sunlight is absorbed as it travels deeper into the ocean, making it darker. Different substances absorb specific wavelengths of light, which is how we perceive color. Absorbed light energy is often converted into other forms, such as heat, explaining why darker colors heat up more in sunlight.
Demonstrations with gummy bears illustrate transmission and absorption. Red light passes through red gummy bears (transmitted) but is absorbed by green gummy bears. Conversely, green light passes through green gummy bears but is absorbed by red ones. This shows how certain colors of light are transmitted or absorbed based on the material.
Rainbows are a beautiful combination of reflected and refracted light. Sunlight enters raindrops, refracts and slows down, with each color bending at a different angle. The light then reflects off the inside surface of the raindrop and refracts again as it exits, speeding up and creating the spectrum of colors we see. Although a raindrop creates a circular reflection, we don't see a full circular rainbow because the Earth obstructs the view.