In our physics classes, one experiment we do is finding speed of rolling objects. This requires us to make two different measurements, distance and time, and then calculate the speed result, v = d/t. On top of this, we normally would measure the time with a stop watch, and do multiple trials at a given distance.
The questions becomes, knowing we are using imperfect measurements that have uncertainty, and divide them to get a result, how in the world can we combine those measurement uncertainties to get the uncertainty in the speed result??? Hmmm....
The process is called propagation of uncertainty. This video will show how to do this with a speed example, but the formula and thinking can be used in any experiment where one multiplies or divides multiple measurements! Keep in mind that if we do time trials in this example, then the uncertainty in the average time is the standard deviation of those time trials.
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