Waves , Sound and lights Flashcards
Pulses
Disturbance in a medium
Amplitude
Maximum displacement of a particle.
Principle of Superposition
Algerbraic sum of the amplitudes of two pulses that occupy the same space at the same time.
What happens when two pulses interact?
They do so constructively and destructively.
Constructive interference?
Increased amplitude
Destructive inteference?
Decreased amplitude
- Transverse Waves
The disturbance of a medium is perpendicular to the direction of the propagation of the wave.
Crest
Highest point of disturbance
Trough
Lowest point of disturbance
Amplitude
Max displacement of a particle at rest
Wavelength
Distance between 2 successive points that are in phase
Frequency
Number of waves passing a given point in a second.
Waves per sec measured in Hertz(Hz)
Period
Time taken for a single wave to pass a given point. Waves per sec Measured in seconds (T)
Formulae for Period is?
T= 1/f
Wavelength formula?
V= f x λ
Longitudinal Waves
a wave in which the disturbance of a medium is parallel to the direction of propagation of the wave
Wavelength
Distance between the centre of two successive compressions or two successive refractions
Sound
Longitudinal waves which require a medium to travel in.
Cannot be produced if vibrations are not taking place.
Density
Sound travels faster in a more dense medium due to particles being closer together. Able to pass energy quicker. Sound travels faster in a solid than in a liquid.
Temperature
Higher the temp higher the kinetic energy . Particles travel faster and pass on energy quicker . Sound travels faster in mediums of high temperatures.
The speed of sound air
340 m/s
Pitch
Determined by sound waves frequency. Higher the freq of sound wave higher the pitch.
Volume
Determined by sound waves amplitude. Higher the amplitude louder the sound.
Tone
How regular sound waves are.
