 # Characteristics of Waves

## Presentation on theme: "Characteristics of Waves"— Presentation transcript:

Characteristics of Waves
Wavelength, Frequency, Speed, Period, and Amplitude

Waves Wave – a disturbance that transmits energy. All waves:
are caused by vibrations travel outward from the source of vibration have a wavelength, frequency, speed, period, and amplitude

Waves Different types of waves: Mechanical wave Electromagnetic wave
Example: Sound or seismic waves Travels through matter Caused by vibrating matter Electromagnetic wave Example: Light Can travel through vacuum Caused by vibrating charges

Waves Disturbance can move in two ways: Transverse wave
Disturbance is perpendicular to direction of wave motion Longitudinal (or compressional) wave Disturbance is parallel to direction of wave motion

Water Waves: Both Transverse and Longitudinal

Properties of Waves Wavelength ()
Distance from one wave crest to the next. SI Unit: meters

Wavelength

Wavelength High density Low density

Properties of Waves Frequency (f )
No. of waves that pass a fixed point per unit of time. SI Unit: s-1 or Hertz (Hz)

Properties of Waves Velocity (v) How fast a wave travels. v = f* 
SI Unit: m/s

Properties of Waves Period (T) Amplitude (A) Demo: Sound Waves Applet
Time required for one complete wave to pass. Inverse of frequency T = 1/f SI Unit: s Amplitude (A) Maximum displacement of wave Demo: Sound Waves Applet

Amplitude A A

Amplitude Higher Amplitude Lower Amplitude

Waves What is the frequency of a wave whose speed is 400 m/s and whose wavelength is 20 meters? v = f (400 m/s) = (20 m)f f = 20 Hz

Waves What is the period of a wave whose speed is 550 m/s and whose wavelength is 50. m? v = f f = v/ T = 1/f T = /v = (50. m)/(550 m/s) = .091 s

Waves A certain wave has a frequency of 445 Hz and a wavelength of 2.20 meters. How fast is the wave traveling? v = f v = (445 Hz)(2.20 m) v = 979 m/s

Waves A certain wave has a period of 3.15 seconds and a wavelength of 500. meters. How fast is the wave moving? v = f f = 1/T f = 1/3.15 s = Hz v = (500. m)(0.317 Hz) v = 159 m/s