1. Waves-Chapter 4

2. What’s a wave?
Wave: a rhythmic disturbance that transfers energy through matter or space
Two general types of waves:
Mechanical waves
Electromagnetic waves

3. Transverse wave

4. Transverse Waves Crest: highest point of a transverse wave
Trough: lowest point of a transverse wave
Amplitude: the amount of energy carried by a wave; corresponds to the height of a transverse wave
Wavelength: the distance between two identical points on a wave

5. Sound wave generated by a tuning fork
      
Sound wave generated by a tuning fork
        
Longitudinal Waves
Before the waves are made the particles are same distance apart. While waves moves through the medium the particles compress together, then they spread further apart (stretched areas)- rarefaction.

6. Longitudinal/Compressional Waves
Rarefaction: expanded portion of the wave; particles are spread apart
Compression: compressed (squeezed) portion of the wave; particles are pushed together
Wavelength: the distance between two identical points on a wave
Amplitude: the amount of energy carried by a wave; corresponds to the amount of compression in a longitudinal wave

7. Vibrations and Mechanical Waves
One wave per vibration. Vibrations create waves.
Vibration stops- waves keep moving.

8. Types of Mechanical Waves
Sound
Water
Seismic

9. Mechanical Waves Require matter to travel through
The matter the mechanical wave travels through is called a MEDIUM
Examples of a medium that a mechanical wave can travel through: sound waves, earthquake waves, water waves
Can be transverse or longitudinal
Transverse Wave
Longitudinal Wave

10. Sound Waves water Waves Seismic Waves
Longitudinal waves (travel in solid, liquids and gases)
Made of series of compressions and rarefactions
Sound is produced when something vibrates. The vibrating body causes the medium (water, air, etc.) around it to vibrate. 
Combination of transverse and longitudinal waves
 Wind produces by pushing on the surface of water
Waves in the Earth, cause earthquakes
Both longitudinal and transverse.
Movement along the Earth’s upper layers along a fault.
Produces seismic waves

11. water Waves
Sound Waves
Seismic Waves

12. Mechanical Waves Two types of mechanical waves:
Transverse : matter moves in the medium at right angles to the direction that the wave is travelling
Examples: water waves, S-type earthquake waves
Longitudinal: vibration is parallel to the direction of motion of the wave; back and forth motion; also called compressional waves
Examples: sound waves, P-type earthquake waves

13. Electromagnetic Waves
Do not require a medium through which to travel (means they can travel through a vacuum such as space)
Examples: radio waves, microwaves, infrared waves (heat), light waves, UV rays, X-rays, gamma rays
Are transverse waves

14. 1 2 3 All electromagnetic waves travel at the same speed.
Their speed is the speed of light = 300,000,000 m/s 2
That’s 186,000 miles/second!!!!!! 3

16. Amplitude- amount of energy carried by a wave
Low Amplitude
Medium Amplitude
High Amplitude

17. Wavelength- distance between two identical points on a wave
Short Wavelength
Long Wavelength

18. Relationship between amplitude, wavelength, frequency, and energy
HIGH AMPLITUDE = HIGH ENERGY
LOW AMPLITUDE = LOW ENERGY
LONG WAVELENGTH = LOW FREQUENCY = LOW ENERGY
SHORT WAVELENGTH = HIGH FREQUENCY = HIGH ENERGY

19. Wave Interactions Reflected by matter Transfer to matter
Pass through matter