If you are interested in electronics only as a hobby or as an electronic technician then general math is all you need to get by. If you are serious about becoming an electrical engineer you will need advanced mathematics training through calculus. See our mathematics section. This is a good link but some browsers have trouble with it. If it doesn't come up for you try the URL in another browser.
Every shop needs a well regulated variable voltage power supply for bench top work.
When building and testing new circuits a power supply is essential. The symbol for electric charge is Q or q, standing for quantity. The volt is a measure of the work needed to move an electric charge. To produce current the charge must be in motion. One watt of power equals the work done in one second by one volt of potential difference in moving one coulomb of charge.