Equations of Electricity

also called Ohm's Law

Voltage or Potential Difference=Current*Resistance

Power=Voltage or Potential Difference*Current


Work Done =Charge*Potential Difference

Gives the Resistance of a wire in terms of it's resistivity, length and cross sectional area

Current=number of free charges per unit volume*cross sectional area*speed of free charges*unit charge

EMF=Output Voltage+Lost Volts (Volts which must must be used to push the current against the internal resistance of the battery)

For Resistors in Series

For Resistors in Parallel

Potential Divider Equation.


For Capacitors in Parallel

For Capacitors in Series

Energy Stored on Capacitor

Energy Stored in Inductor

Reactance of Capacitor

Reactance of Inductor

Ohm's Law for Circuit with Inductance

Current into a Junction =Current out

Kirchoff's First Law

Sum of EMF's in a closed circuit = Sum of Potential Differences

Kirchoff's Second Law

Force between point chargesand separated by distance

Potential energy for two chargesand separated by distance

Electric field at distancefrom point charge

Electric potential at distancefrom point charge