Sound: A Quick Recap

Sound is the most common example of a longitudinal wave (if you need a second example in an examination, mention seismic P waves from earthquakes). It is therefore important that you can describe and explain sound waves. This includes how the human ear works (in physics terms) and how microphones and loudspeakers link sound to electrical signals.

There are some simple and clear explanations on the BP Educational Services website and those are the resources that we will use here. You may find them a bit obvious in places but they will give you a good recap of the things that you should already know and also highlight some applications of sound (through the air and through solids).

First… What exactly is sound and how do we represent it? Go to bp.com/bpes then click on Enter a student code (top right corner) and use the code 47230. Watch the short video.

Now remind yourself about frequency and amplitude. Go back to the website but this time enter the code 11390 and watch the next video.

You will learn about microphones and loudspeakers later in the course (when we learn about electromagnetism) but it’s useful to understand the basics while we’re learning about sound. So go back to the website and enter the code 55725 to watch this video.

Finally, there are two videos about applications of sound. One discusses reflection and absorption of sound in a concert hall: you can access that video with the code 82304. The other video is about how sound is used to find oil and gas underground: use code 29280 to watch this final video.

There are also some worksheets on the pages that you viewed: they are the same ones on all three pages. You may wish to complete, print out and stick these worksheets into your exercise book. Alternatively, you can email your work for feedback if you wish.