I’m trying to figure out the speed of rotation of a wheel using a Hall Effect sensor. Here is what I know:

I have 3 magnets spaced evenly on the wheel (71mm apart around circumference of wheel)

The hall effect sensor is working and counting (tested)

Their are 1,609,344 mm in a mile

1000 ms in a second (everyone knows that)

I just can’t seem to figure out the formula…

I have arduino counting each time it senses a magnet and incrementing each time a magnet passes. So I know the hardware is correct.

all I need to figure out, which I’m having trouble with, is the formula to calculate mph based on magnet spacing, etc… [smiley=undecided.gif]