Work, Energy, and Power-Princeton AP Physics I

unit of power

the joule per second (J /s), which is renamed the watt, and symbolized W.

Power

the rate at which work gets done (or energy gets transferred, which is the same thing)

crests

maximum vertical displacement above the horizontal

Troughs

maximum vertical displacement below the horizontal

wavelength

the crests and troughs repeat themselves at regular intervals along the rope, and the distance between two adjacent crests (or two adjacent troughs) is the length of one wave

Amplitude of the wave

maximum displacement from the horizontal equilibrium position of the rope is measurable

period

the interval taken to complete one cycle of a regularly repeating phenomenon

frequency

the number of occurrences within a given time period

Superposition of Waves

when two or more waves meet, the displacement at any point of the medium is equal to the algebraic sum of the displacements due to the individual waves

standing wave

a wave in which the ratio of its instantaneous amplitude at one point to that at any other point does not vary with time

compressions

the variations in the conducting medium can be positioned at which the molecules of the medium are bunched together (where the pressure is above normal)

Rarefactions

positions where the pressure is below normal

The Doppler Effect

When a source of sound waves and a detector are not in relative motion, the frequency that the source emits matches the frequency that the detector receives.