# equations

Just looking to see if anyone has a big cheatsheet of electronic equations they are willing to share.
Sure, ohm's law is easy enough, but there are so many more equations out there, and I can only remember so many of them.

V=IR
V/R = I
V/I = R
P = IV
P = I^2*R
P=V^2/R
PV=nRT
Period = 1/Frequency

What else do you need?

ic approx equal to ie for bipolar junction transistor (under usual operating conditions).
ic approx equal to beta*ib for bipolar junction transistor.

ic is collector current, ib is base current, ie is emitter current

I see you use "V", where I learned "E" for voltage.

As for what else I need..... I was looking for a whole laundry list beyond ohms law.

transistors, mosfets, capacitors, inductors.....

Just a cheatsheet with the various equations. I've stumbled upon a few that were well laid out and easy to find what you were looking for, some just covering ohms law. I find it somewhat handy when I'm tired from dealing with the crisis of the day and just need to double check myself.

Welcome tinman13kup.

I learned "E" for voltage

Electromotive Force?

electronic formulas cheat sheet

ideal capacitor: C dV = I dt
ideal inductor: L dI = V dt
resonant LC circuit: f = 1/(2 pi) sqrt (1 / LC)
conductor in a magnetic field: F = B l I, V = B l v
RC time constant tc = RC
RL time constant tc = L/R
resistance of wire R = rho l / A, rho = bulk resistivity, l = length, A = cross section area
ideal diode: I proportional to e^(qV/kT), q = charge on electron, k = Boltzman's constant, T in kelvin,
or at room temp: I roughly proportional to e^(39 V), doubles every 18mV or so, x10 every 59mV

You can derive:

energy in capacitor: E = 0.5 C V^2
energy in inductor: E = 0.5 L I^2
characteristic impedance of transmission line = sqrt (L/C) - where L and C are inductance and capacitance
per unit length.

Twinkle Twinkle Little Star Power Equals I square R.

Tom...

PV=nRT

You sneaked in the ideal gas law! Don't think I've needed that for electronics yet

MarkT:
You sneaked in the ideal gas law! Don't think I've needed that for electronics yet

Might be useful for calculation of how much magic smoke was released

TomGeorge:
Twinkle Twinkle Little Star Power Equals I square R.

Tom...

NOOOOO!!! Make it stop!!! The voices in my head!!

Tom too

And JUST when I thought this was getting really boring, I found the holiday shopping solution for two of my Grandchildren: HERE

That really looks like someone from way back:

LarryD:
That really looks like someone from way back:

Wonder how long it would take people to notice that??