wave basics

wave definition

waves are a disturbance that transfers energy through a medium or space without a net transfer of matter

oscillation definition

repetitive back and forth motion around a central position

amplitude

max displacement of the wave from its equilibrium position unit: meter m

wavelength

lambda. wavelength is the distance between two consecutive corresponding points of a wave that are in the same phase such as the distance from one crest to the next or one trough to the next. unit: meter cm

frequency

frequency is the number of oscillations per second measured in hertz Hz

period + formula

T. Period is the time for one complete cycle of a repeating event such as an oscillation measured in seconds s.

T = 1 / frequency

trough crest

lowest and highest

wave speed formula

wave speed = frequency (Hz) x wavelength (lambda m)

transverse waves + examples

transverse waves is a wave in which the oscillations of the particles are perpendicular to the direction in which the wave travels. It can travel in solids and liquids. light waves, water surface waves, electromagnetic waves

longitudinal waves + waves

longitudinal waves is a wave in which the oscillations of the particles are parallel to the direction of energy transfer. It requires a medium and travels faster in solids, slow in gases. sound waves

mechanical waves

mechanical waves require a medium and is transverse or longitudinal. sound, water, seismic

electromagnetic waves

electromagnetic waves don’t require a medium and is always transverse. light, radio, xrays

wavefronts

wavefronts are surfaces of constant phase where all points are oscillating in sync

rays

rays are lines that show the direction the wave is moving. they are always perpendicular to the wavefronts

sound waves + speed in air + range of human hearing

sound waves are vibrations that travel through a medium carrying energy in the form of compressions and rarefactions. they are longitudinal waves. 330-340 m/s 20Hz - 20000 hz

how doe sthe loudness of sound belong to

amplitude

how does pitch relate to

frequency

ultrasound + use

sound waves with frequencies above 20 kHz. medical imaging, cleaning, sonar

echos

reflections of sound waves from a surface

sonar definiton

distance using reflected sound

formula for sonar

distance = speed x time / 2