Save guides, add subjects and pick up where you left off with your BBC account. The circumference of a circle = \(\pi d\) or \(2\pi r\). Look at the sector of the circle shown below. To calculate ...

It is another name for the perimeter of a circle. The circumference of a circle is calculated using the formula: \(\text{circumference} = \pi \times \text{diameter}\) This number is Pi.

If you’ve dealt with reactance, you surely know the two equations for computing inductive and capacitive reactance. But unless you’ve really dug into it, you may only know the formula ...