Karate chopping the end off a wooden school ruler has always been a classroom sport.
To karate chop a ruler the following equation applies:
Now we can have some fun, mathspigs.
We will do some calcs to compare the force, F, required to karate chop a piece off a wooden ruler staring at 10cm length and working back to shorter and shorter lengths. These calcs also work in inches.
But when you karate chop a ruler you hold one end down with you other hand. So what is the ideal point on the ruler to act as the fulcrum for easiest karate chop force? You can find more information on levers at the Robinson Library.
You can, surprisingly, use a piece of newspaper to hold the ruler in place. Check it out atKingsford School.