Instructions

Each set of peeks corresponds to a strong blow onto the fan blade. You could use
this to measure the maximum speed to see who can blow the hardest.
How it Works
D.C. Motors like the one in this kit, can act as both motors and generators. They are
not very efficient and only generate a small amount of power. The voltage that the
motor generates will be higher, the faster the fan blades spin.
The forever block uses analog read pin P0 to measure the voltage on pin 0. This
number is theoretically (between 0 and 1023), but in practice, unless the fan blade
is exposed to hurricane force winds, the maximum reading will be around 250. This
number is then sent to your computer over USB using the serial write value block
and then a bar graph of the value is shown on the micro:bit display.
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