Hobbies And Interests
Refraction
A beam of light will change direction when it passes from a less dense substance to a denser substance. This change of direction, known as refraction, can be demonstrated with a flashlight and a clear glass of water. To do this, fill the glass with water and turn the lights off in the room. This experiment can be better seen at night or in a windowless room. Shine the flashlight at an angle into the glass of water. The light will change direction when it passes from the less dense air into the denser water.
Reflection
All waves, including light waves, experience reflection when they bounce off of an obstacle. A wave will leave the surface of a flat reflecting object at the same angle at which it approaches the object, which is why mirrors work in the way that they do. Our eyes perceive the light coming from an object, which enables us to see the object. When a flat mirror reflects light, the light enables us to see the object. A light beam can be used to more clearly demonstrate this. Find a beam of sunlight coming through a window on a sunny day. Try to redirect the light beam with a small, hand held mirror. Hold the mirror under the light, and then move it around until you locate the reflection of the light somewhere on a wall. The beam will appear as a spotlight that can be moved around to shine on different walls and objects, thereby demonstrating the law of reflection.
Magnification
Light beams can be intensified to increase their radiation and strength. When an object is looked at through a magnifying glass, the light rays reflecting off the surface of the object under the glass are magnified by the shape of the glass. This makes the object look larger than normal. A light beam can demonstrate this phenomenon. On a bright, sunny day, take two ice cubes outside, along with a magnifying glass. Place both ice cubes on the ground or in separate bowls. Now hold the magnifying glass above one of the ice cubes. Slightly change the angle of the magnifying glass until you are able to concentrate a single spot of light on the ice cube. Be very careful not to shine this light in anyone's eyes, and keep your hands away from the concentrated light beam. Hold the light on the ice cube and watch how much quicker this cube melts compared with the other one. This is the magnified strength of a light beam.
Rainbows and Color
Light refraction occurs when light passes through water. When this happens, the individual colors within the beam of light are separated, creating a rainbow. Although rainbows are seen in the sky when it is raining, the sun is still shining. This concept can be demonstrated with a beam of light and a glass of water. Hold a clear glass of water up to the light coming through a window. Hold a piece of plain white paper where it will capture the light as it is refracted through the water. A rainbow should appear on the piece of paper. This demonstrates how refraction of light produces color.
Traveling Light Projects
As light moves further away from its source, its strength is diffused. In a dark room, place a flashlight on a table or flat surface. Hold a piece of paper in front of the light beam, just a few inches away. Draw a circle around the beam as it appears on the paper. Now move the paper away a few more inches, and again draw a circle. Repeat this several times at different distances. Compare the sizes of the circles you have created. As the circles get larger, they show a weaker representation of the light beam. Although the energy in the light beam remains the same, it is diffused over a larger surface area, which makes it less concentrated.