waves, sound and light Flashcards
transverse pulses, waves, sound, and electromagnetic radiation
a pulse
single disturbance in a medium
transverse pulse
pulse in which the displacement of particles in a medium is perpendicular to the direction of the movement of the pulse
amplitude (A)
the maximum displacement of a particle from its rest position
pulse length
distance between start and end of a pulse
pulse speed
distance covered by a pulse in 1 second
superposition
the algebraic sum of amplitudes of 2 pulses that occupy the same space at the same time
constructive interference
occurs when the crest of 2 pulses meet each other on the same side of the rest position.
-> resulting amplitude is larger
destructive interference
occurs when a crest of 1 pulse and a trough of another pulse, meet on opposite sides of the rest position
-> resulting amplitude is smaller
transverse waves
wave in which particles of the medium vibrates perpendicular to the direction of motion of the wave
-> is a succession of transverse pulses
trough
the lowest point of a wave at its maximum displacement from the position of rest in the opposite direction
crest
the highest point of a wave at its maximum displacement from the position of rest
wavelength
distance between 2 consecutive points in phase
-> unit of measurement = metre (m)
2 points in phase
when they are separated by a whole number multiple of complete wavelengths
point out of phase
they are not separated by a whole number multiple of complete wavelengths
frequency
number of waves per second
-> unit of measurement = hertz (Hz)
period (T)
time taken for one complete wave pulse to pass a point
-> unit of measurement = seconds (s)
wave speed (v)
distance travelled by a point on the wave per unit time
longitudinal wave
wave in which the particle of the medium vibrate parallel to the direction of movement of the wave
compression
region of high pressure and particles are close together
rarefaction
region of low pressure and particles are far apart
pitch
of a sound is directly proportional to the frequency of that sound
ultrasound
sounds above 20 000
electromagnetic spectrum
range of different types of EM waves
photo
energy packets found in EM waves (quanta) that transfer energy to particles of matter