Longitudinal waves

Longitudinal waves can also be simulated in Excel. This time the points are being displaced horizontally we will start with 3 points. Set up the spreadsheet as shown below. The slider is set to vary cell G5 from 0 to 30,000 in steps of 1. To make the time (F5) change in smaller steps it is calculated from G5/1000.

The displacement is the original position – Asin(2πft) Insert an xy scatter based on columns B and C and format the x axis so that it doesn’t rescale automatically (min of -0.1 and max of 0.2 works well).

Animate the points by moving the slider, the 3 points should oscillate in phase. To introduce phase difference the term 2πx/λ is again introduced in the equation.

=A2-F\$2*SIN((2*PI()*F\$4*F\$5)-2*PI()*A2/F\$3)

This equation is copied down to the three cells to give the following phase difference. To make a wave copy the three columns down to 100 values then insert an xy scatter based on columns B and C. Again fix the X axis between 0 and 10 to stop it rescaling.

Change the amplitude to 0.1 and the wavelength to 2 and use the slider to animate the wave, It should look like the one below. All materials on this website are for the exclusive use of teachers and students at subscribing schools for the period of their subscription. Any unauthorised copying or posting of materials on other websites is an infringement of our copyright and could result in your account being blocked and legal action being taken against you.