I have an interview for a post 16 teaching post, 25 minute lesson on "introduction to the modulus function, either algebraic or graphical". The school is very keen on industrial applications in every lesson where possible so I'm keen to put something functional into the lesson.
Obviously the simple way to go is to calculate some values to an quadratic curve, plot the modulus of it and see how it "bounces" on the x-axis, but I was looking for something more applied.
I can think of finding the difference between two values using Mod(x1-x2) but that seems a bit statistical for an algebra introduction.
I'm considering something along the lines of air pressure calculations for something like Bloodhound SSC - they probably don't care if the pressure is positive or negative on a panel, they just want to know how much pressure each panel is under but this feels a bit artificial and contrived.
Any other ideas?