Waves and Applications
Waves are rhythmic disturbances that cause the moving of energy from one location to the other without the movement of matter. They are all around us – bringing sound to our ears, light to our eyes, and most amazingly, even energy around the ocean. Learning about waves explains the world around us and drives much of the technology we cannot live without.
1. Sound Waves
What They Are: Sound waves are movement, which carries through a medium (such as air, water, or solids), and can be listened to through our ears.
How They Work: Every time an object vibrates, then it pushes and pulls the medium particles around it creating a wave which takes sound.
Everyday Examples: Talking, music, alarms, and even medical ultrasound.
2. Light Waves
What They Are: Light waves are electromagnetic waves that could move in a vacuum (such as space), and a human eye can perceive them.
How They Work: The light waves travel in a straight line and they can reflect or refract on passage through various forms of materials or be absorbed.
Everyday Examples: Seeing colours, using flashlights and the operation of the lenses in glasses and cameras.
3. Wave Behavior
Reflection: When a wave hits a surface (like echo).
Refraction: When a wave has a directional change when it is transferred from one medium to another (such as a straw being bent when under water).
Diffraction: When a wave fans out after it has gone through a narrow opening or around an obstacle.
Absorption: When energy of a wave is absorbed by a material and converted into heat.
4. Electromagnetic (EM) Waves
What They Are: EM waves are the waves that can propagate through vacuum and cover all the varieties of waves – from radio to gamma rays.
How They Work: They include oscillating electric and magnetic fields and are moving at the speed of the light wave.