In this experiment we are using JAVA applet of wave model which is available at: http://www.colorado.edu/physics/2000/applets/fourier.html
Here we can change wavelength and amplitude of two waves and in the third graph we can see a wave combined from these two waves. By changing any of two waves we can observe how it affects wave on the third graph.
1. Let’s set in wave length equal to 50 and amplitude to 1 in the first and second graphs. In this case we can observe that in the third graph wavelength is two times bigger and amplitude is also two times more.
This happened because when two waves are merging and they are in the same position, then amplitude and wavelength of composed wave will be a sum of first two waves. If we drag one of waves so that it will become inverted copy of other wave then we will observe that composed (third) wave will have amplitude and wavelength equal to zero.
2. If we change on of the waves so that its amplitude will be 0,5 and wavelength 50, then we can observe that wave on the third graph will have amplitude equal to the sum of amplitudes of two other waves and will be 1,5 and wavelength will remain the same.
3. In the third part of this experiment we have to change one of the waves. We have to change its wavelength to 0.25. On the graph reflecting combination of two waves we can wee that upper part of waves has amplitude equal to 2 and bottom part of waves are decreasing to zero because they are covered with second wave which at this pints has amplitude equal to 1 and when it’s added to the first wave, which has amplitude equal to -1 at those points, the sum becomes zero and lays on the zero point of Y axis.
4. In the fourth experiment we have to use the same parameters as in third experiment, but change the amplitude of the second wave to 0.5. In such case we will have similar outcome as in the third experiment but the difference will be, that every bottom part of the wave will decrease to -0.5 instead of decreasing to zero, because here we have sum of two wave amplitudes -1 and 0,5 and their sum is equal to -0.5.
