1.Wave
-In physics a wave is a disturbance or oscillation that travels through spacetime, accompanied by a transfer of energy.
2.Sources of wave
Sound waves, visible light waves, radio waves, microwaves, water waves, sine waves, cosine waves, stadium waves, earthquake waves, waves on a string, and slinky waves and are just a few of the examples of our daily encounters with waves. In addition to waves, there are a variety of phenomena in our physical world that resemble waves so closely that we can describe such phenomenon as being wavelike.
3.Amplitude
-The amplitude of a periodic variable is a measure of its change over a single period (such as time or spatial period)
4.Period of wave
-The period of a wave is the time taken for one complete cycle of the wave to pass a reference point. Equivalently, it is the time between successive maxima or minima of the wave.
5.Frequency
-Frequency is the number of occurrences of a repeating event per unit time.
6.Wave length
-Wavelength is a measure of the distance between repetitions of a shape feature such as peaks, valleys, or zero-crossings, not a measure of how far any given particle moves.
7.Crests
-A crest is the point on a wave with the maximum value or upward displacement within a cycle.
8.Trough
-A trough is the opposite of a crest, so the minimum or lowest point in a cycle.
9.Classifications of Wave
a.Mechanical Wave
A mechanical wave, also called material wave, is a wave that needs a medium to travel.

b.Electromagnetic Wave A wave of energy having a frequency within the electromagnetic spectrum and propagated as a periodic disturbance of the electromagnetic field when an electric charge oscillates or accelerates.

c.Transverse Wave
A transverse wave is a moving wave that consists of oscillations occurring perpendicular (or right angled) to the direction of energy transfer.

d.Longitudinal Wave
Longitudinal waves, also known as "l-waves", are waves whose direction of vibration is the same as their direction of travel, meaning that the movement of the medium is in the same direction as, or the opposite direction to, the motion of the wave.

e.Surface Wave
- In physics, a surface wave is a mechanical wave that propagates along the interface between differing media, usually two fluids with different densities.

10.Wave Speed
- The speed at which the wave form of a progressive wave travels.
a.Formula
Speed = Wavelength • Frequency
Speed=Wavelength/Period
b.Units
(meter/second)
c.Sample Problems
1.A wave with a frequency of 14 Hz has a wavelength of 3 meters. At what speed will this wave travel? f = 14Hz
= 3m v = f v = 3m x 14 Hz v = 42 m/s
2. A wave has a frequency of 46 Hz and a wavelength of 1.7 meters. What is the speed of this wave? f = 46Hz
= 1.7m v = f v = 1.7m x 46 Hz v = 78.2 m/s