Ohm's Law

Ohm's Law defines the relationships between (P) power, (E) voltage, (I) current, and (R) resistance.

( I ) Current is what flows on a wire or conductor like water flowing though a pipe. Current flows from negative to positive on the surface of a conductor. Current is measured in (A) amperes or amps.

( E ) Voltage is the difference in electrical potential between two points in a circuit. It's the push or pressure behind current flow through a circuit, and is measured in (V) volts.

( R ) Resistance determines how much current will flow through a component. Resistors are used to control voltage and current levels. A very high resistance allows a small amount of current to flow. A very low resistance allows a large amount of current to flow. Resistance is measured in ohms (Ω).

( P ) Power is the amount of current times the voltage level at a given point measured in wattage or watts.

Note: volts2 or amperes2 means to the second power.

P = Watts

Watts = Volts2 / Ohms
Watts = Amperes2 X Ohms
Watts = Volts X Amperes

I = Amperes

Amperes = Volts / Ohms
Amperes = Watts / Volts
Amperes = √ Square Root of Watts / Ohms

E = Volts

Volts = √ Square Root of Watts X Ohms
Volts = Watts / Amperes
Volts = Amperes X Ohms

R = Ohms

Ohms = Volts / Amperes
Ohms = Volts2 / Watts
Ohms = Watts / Amperes2

 

Disclaimer: I will take no responsibility for any injuries or damage suffered by anyone as a result of the misinterpretation or misapplication of the information contained in these pages. Proper high voltage safety procedures and precautions must be practiced at all times when servicing vacuum tube amplifiers. If you are not completely familiar with these precautions, seek guidance from someone who is.

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