1. Waves
Unit 8

2. Wave a rhythmic disturbance that carries energy through matter space
waves transmit energy
there are multiple kinds of waves:

3. Electromagnetic Waves
a wave consisting of changing magnetic and electric fields that move through space at the speed of light
Example: Radiation or magnetic fields

4. Mechanical Waves
waves that require a medium (material that carries the wave)
water waves, sound waves, or a spring

5. Medium of the Wave
The “medium” is whatever the wave travels through (water, air, or a spring)

6. Wave Pulse
a single bump or disturbance that travels through a medium

7. Continuous Wave
a repeating sequence of wave pulses

8. Transverse Wave
a wave that vibrates perpendicular to the direction of wave motion
Example: waves created in a rope or spring if you move it up and down but the waves move right and left, perpendicular

9. Longitudinal Wave
a wave that displacement is parallel to the wave direction
only transmitted in fluids (liquids and gases)
Example: Sound waves

11. Surface Waves
made up of characteristics of both transverse and longitudinal waves
Example: waves at the surface of water

12. Amplitude
the maximum displacement from its rest position or equilibrium
depends on how the wave was generated, NOT by the speed
the larger the amplitude the more energy

13. Wavelength
the shortest distance between point where the wave pattern repeats itself
1.Trough
Lowest point in a wave
2. Crest
Highest point in a wave

14. Wavelength (λ)
wavelengths are measured trough to trough or crest to crest
represented by the Greek letter lambda λ

15. Example
Create a wave with the following information: wavelength (λ): 6 and amplitude: 5

16. Period (T)
the time (T) it takes the source to return to the same point in its oscillation
equal to the period of the source that generates the wave

17. Period Equation 1
T = f
f = frequency (Hz)
T = period (s)

18. Frequency (f) number of complete oscillations in one second
measured in hertz (Hz)

19. Frequency (f) 1
f = T
f = frequency (Hz)
T = period (s)

20. Velocity using period λ v = T v = velocity (m/s) λ= wavelength (m)
T = period (s)

21. Velocity using frequency
v=λ·f
v=velocity (m/s)
λ= wavelength (m)
f = frequency (Hz)

22. Example:
A sound wave has a frequency of 262 Hz and a wavelength measured at 1.29 m. What is the speed of the wave using frequency?
What is the period of the wave?
What is the velocity of the wave using period?