(40 marks) Phy. questions about WAVES (1) --

Question

I really cannot understand things about Waves ...
So I need a clear answer which is easy to understand.
(DO NOT ACCEPT COPY-AND-PASTE ANSWER ,and ENGLISH PLX!)

My first question :
(a)
How to draw a displacement-distance graph and a displacement-time graph ?

(b)
How to convert them each other ?
(i.e. how to draw the other when either one is given)

(c)
Are there any tips / techniques on drawing these graphs ?


Thank you for helping .

Answer 1

(a) How to draw a displacement-distanc e graph and a displacement-time graph ?
To draw a displacement-distance graph, use displacement as y-axis and distance as x-axis,then use the given informations to plot the graph.
To draw a displacement-time graph, use displacement as y-axis and time as y-axis,then use the given informations to plot the graph.
(b) How to convert them each other ?
We cannot draw the other when either one is given as the informations showed by them are two different things.
Displacement-distance graph shows the displacements of particles of a wave from their equilibrium position at a certain time, it can show the amplitude and wavelength of the wave.
Displacement-time graph shows the displacement of a particular particle from its equilibrium position with time, it shows only amplitude and period(or frequency) of the wave.
However, if you have a displacement-distance graph and the period of the wave,then you can draw a displacement-time graph.Or you have a displacement-time graph and the wavelength of the wave,you can draw a displacement-distance graph.
(c) Are there any tips / techniques on drawing these graphs ?
You should remember that amplitude is the displacement in both two graph while wavelength is distance in displacement-distanc e graph and period is equal to time/no. of completed wave motion in the displacement-time graph.
Actually,plotting these graphs is not a difficult work,don't worry.
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