You can do Doppler demonstrations in the in the classroom by whirling a commercial “Doppler Ball” or your own home made “buzzer on a string” device around your head. Here we look at experiments that demonstrate quantitatively the frequency shift. The second, which uses a free frequency spectrum analyser, shows the shift in real time and opens up the possibility of investigations into the relationship between frequency and velocity.
It has to be said that the following experiment is much better.
The following document is aimed mainly at Advanced Higher, but there’s an activity where the detection of exoplanets using the Doppler effect is modelled: