physics Flashcards
what is a transverse wave
oscillations are PERPENDICULAR to the direction of energy flow which doesn’t need a medium to occur
what is a longitudinal wave
the oscillation follow the direction of the wave with the vibrations parallel to the waves position of the oscillation of particles around a fixed point are parallel to the direction of energy which also require a medium to flow through.
What is a medium
Substance /material through which the wave travels with
eg: Water waves move through the substance of : Water
Sound waves travel through the substance of: Air as well as liquids and solids
does the particles”dots” move in a transverse wave
The particles do move but only in a up and down motion perpendicular to the direction of enrgfy flow but at different speed causing the illusion of the wave moving in a specific direction
Oscillation definition
The repetitive motion around an equilibrium position
frequency definition
number of whole cycles in 1 second. / f = 1÷T
period definition
time taken taken for one whole cycle of oscillation
displacement definition
How far an oscillation has moved from its mean value
Wavelength definition
Distance along a wave in its direction of travel( propagation ) between two consecutive” in- phase” points
wave graph can have either distance/ time on its x-axis with displacement on its y axis
distance= lambda =wavelength (m)-length of between two successful crests/troughs
time = Time period(s)=time taken for one wave to pass
amplitude definition
max displacement in am oscillation from equilibrium point at resting value
wave speed equation
v = f x lambda
v = wavelength (ms-1) - same as m/s
- ms-2 same as m/s^2
f = frequency (hertz, Hz)
lambda = wavelength (m)
give rearranged wave equations
lambda = v/f
f= v/lambda
practice question : find frequency when wavelength is 0.05m and wave speed=0.075m/s
v=f x lambda
0.075 = ? x 0.05
rearrange : f= v/lambda
? = 0.075 / 0.05 =1.5
frequency = 1.5 Hz
what is the speed of light
3 x 10^8 m/s
if a wave has a period of 0.25 seconds the how many oscillations will pass every second
f=1/T
?= 1/0.25
frequency = 4Hz
frequency defintion = number of wjole cycles in 1 second or f=1/T
wave cycle positions
phase/degrees
phase/radians
Number of wavelengths
what is the start number of each wave cycle position
0
1/4 of a cycle in phase/degrees
90
1/2 a wave cycle in phase/degrees
180
3/4 of a wave cycle in phase/degree
270
1 whole wave cycle in phase/degrees
360
1.5 cycles in phase/degrees
540
2 whole cycles in phase/degrees
720
1/4 of a cycle in phase/radians
pi/ 2
1/2 cycle in phase/radians
pi
3/4 wave cyle in phase/radians
3 pi/2
1 cycle in phase/radians
2pi
1.5 cycles in phase/radians
3pi
2 cycles in phase/radians
4pi
number of wavelengths in 1/4 cycle
lambda/4
number of wavlengths in 1/2 cycle
lambda/2
number of wavelengths of 3/4 cycle
3lambda/4
number f wavelengths in 1 cycle
lambda
number of wavelengths in 1.5 cycle
3lambda /2
number of wavelengths in 2 cycles
2lambda
what is phase difference/
the difference in phase angles between two waves with the same frequency and wavelength
- phase difference is described in degrees or radians
frequency equation
f= 1/T
f=v/lambda
