The Behavior of Waves
Reflection Reflection – when a wave strikes an object and bounces off of it All types of waves can be reflected
Law of Reflection The wave which strikes a surface is called the incident ray The wave that bounces off of the surface is called the reflected ray Law of Reflection – the angle of incidence is always equal to the angle of reflection
Refraction Refraction – the bending of waves caused by a change in its speed as it moves from one medium to another The greater the change in its speed, the more the wave bends
Light slows down – bends towards the normal Light speeds up – bends away from the normal
How does a prism work? 1.) Light waves enter into prism and slow down. 2.) This causes the waves to bend 3.) The different colors of light bend different amounts so the colors are separated
Diffraction Diffraction – when an object causes a wave to change direction and bend around it
Diffraction and Wavelength Amount of diffraction depends on the size of the object the waves hit and the wavelength of the waves If the object is smaller than the wavelength the waves will bend around it So sound waves which are larger will diffract much better than light waves which are much smaller
Absorption Waves can also be absorbed when they strike an object. Energy is converted into thermal energy This is why wearing dark clothes in the winter months keeps you warmer
Interference Interference – when two or more waves combine to form a new wave
Constructive Interference Constructive interference – when two or more waves add together In transverse waves the crests will line up with one another In compressional waves the compressions will line up with one another The overall effect is to increase the amplitude (energy) of the wave
Destructive Interference Destructive interference – waves subtract from one another when they overlap
Standing Wave A standing wave is a special type of wave pattern that forms when waves equal in wavelength and amplitude, but traveling in opposite directions, continuously interfere with each other The places where the two waves always cancel are called nodes.