# Electronic Formulas (recommend a book?)

Discussion in 'General Electronics Discussion' started by wojnarj, Jan 23, 2014.

1. ### wojnarj

12
0
Dec 15, 2013
Hello

Is there a very basic book out there that has all the basic to intermediate formulas one needs to learn about electronics?

From figuring out resistors in series and parallel to current dividers and capacitors in series?
Also, with examples and tweaks on the formulas when you only have two of three variables such as:

what is the maximum current that can a 220 ohm resistor handle if the power rating was 1/4 watt?

or if you need to find out the amount of a second resistor and you have the v and current through the circuit?

thank you

2. ### (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

25,501
2,841
Jan 21, 2010
What you want is not formulae, but knowledge.

the basic formulae for DC are V = IR and P = IV From those you can derive anything related to resistors.

For resistors in series (same as capacitors in parallel) the formula is Rt = R1 + R2 + R3 + ... (Rt is the total resistance)

For resistors in parallel (or capacitors in series) the formula is 1/Rt = 1/R1 + 1/R2 + 1/R3 + ...

For AC it gets a lot more complex and an understanding of differential equations comes in handy.

There are a whole lot of other rules which embody the mathematics of circuits. Things like Thevenin/Norton equivalent circuits, and Kirchoff's laws, and a heap of other things that make complex calculations easier to perform.

Many books have this stuff in them (The Art Of Electronics covers it in chapter 1) but it can be a rather dry read, so I wouldn't really advise people to learn it straight from a book (or at least not any book I know)

3. ### mahone

25
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Dec 21, 2013
practical electronics for inventors covers most formulae, its the most useful book I've found.

can anyone recommend a book that covers ac and calculus for electronics? I admit that I use online calculators a little bit too much. its convient for speed and its years since I took calculus, I still remember the methods, what I am looking for is an ac "cheat sheet"

4. ### jcurrie

128
1
Feb 22, 2011
take a look at UGLY'S electrical referance book its all about industral apps .
jc