
Carlos M. answered 06/13/20
Music Theory/Composing, Production, Saxophone - Adjunct Professor
There are four sharps in the key of E major. Those sharps are F#, C#, G#, and D#. In order to find this out you would need to reference the circle of 4ths or 5ths. Sharps move in fifths on this diagram starting from C moving clockwise. The key of C has no sharps and flats which means, G would be one sharp, D two sharps, A three sharps, and finally E being four sharps. A good way to first visualize past the diagram itself this would be at the piano, so you can physically see the space between these intervals. Also having a good grasp of your major scales can help the process as well by playing up to fourth or fifth note of each scale!
As far as understanding the order of the sharps themselves, there are several ways of thinking about it. A good way of learning these is through mnemonic devices such as “Father Charles Goes Down And Ends Battle” - this is the order of the sharps. If you read this backwards exactly: “Battle Ends And Down Goes Charles’ Father,” this is the order of the flats. If you memorize the principle that sharps move in fifths and flats move in fourths, then you would only need to know the first sharp (F#) or flat (Bb) in order to figure out the rest.