1. Introduction to Waves

2. A wave is actually just a carrier of energy. Just like a Fireman in a bucket brigade. The fireman does not move, but the buckets do to put out the fire.

3. A wave must pass through a medium, or substance that carries the energy. The medium is displaced, but does not move. A pulse is a single vibratory disturbance, which moves from point to point through a medium.

4. When several pulses are added together in a medium then a wave is produced. Waves transfer energy without transferring mass!

5. Picture of a Wave Pulse Velocity of the Wave Motion of the particles

6. Types of Waves Some waves need material mediums in which to travel. –Water –Slinky –Sound Light, radio and other electromagnetic waves are periodic disturbances in an electromagnetic field. We will see examples of this later. These last examples do not need a medium to travel through.

7. Transverse vs. longitudinal Waves are classified by the way they vibrate. The most common types or longitudinal waves, and transverse waves.

8. Transverse vs. longitudinal Particles in longitudinal waves vibrate parallel to the direction of the wave motion. Each particle moves back and forth parallel to the wave direction. Sound is an important example of a longitudinal wave. Seismic waves (P- waves) are longitudinal waves. Particles vibrate Wave motion

9. Transverse waves Particles in transverse waves vibrate perpendicular to the direction of the waves. Each particle moves perpendicular to the wave’s direction. Electromagnetic waves, such as light and radio are examples of transverse waves. Seismic waves (S-waves) are transverse waves. Transverse waves can travel in the same direction but in different planes.

10. Electromagnetic Wave Consists of Electric Field, and Magnetic field. Diagram on Board

11. Speed of Waves The velocity of any wave is given by V = f (f = frequency) ( = wavelength)

12. Wave Characteristics Frequency (f) or ( ) – The number of waves passing a point per unit time – unit is hertz (Hz) Period (T) – The time for one complete wave to pass a point. T = 1/f Amplitude – The distance the waves moves from equilibrium. Related the energy given to the wave

13. Wave Characteristics Wavelength – The length of the wave from crest to crest or trough to trough. Wave front – The leading edge of a wave.