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OHM'S LAW

Ohm's Law relates the three fundamental electrical quantities: voltage, current and resistance. Power relationships are also given. V = I � R     I = V     R = V                      R           I P = I � V     P = I2 � R     P = V2                                                R I = Current (A) P = Power (W) R = Resistance (W) V = Voltage (V)
 KIRCHHOFF'S LAWS
 Kirchhoff's Current (1st) Law Kirchhoff's Voltage (2nd) Law The current flowing into a node or branching point is equal to the sum of the individual currents leaving the node or branching point. The algebraic sum of all the voltages around any closed path in a circuit equals zero. NORTON EQUIVALENTS The Norton Equivalent of a circuit consists of a Norton current source in parallel with a Norton resistor and is valid for any load. In AC circuits a Norton equivalent circuit is valid for a single frequency.
 Original Circuit Norton Equivalent Circuit The Norton current is the short-circuit current at the output - the same as what is calculated for the Th�v�nin short-circuit current (see Th�v�nin Equivalent page).
The Norton resistance is the same as the Th�v�nin resistance.

 TH�V�NIN EQUIVALENT The Th�v�nin Equivalent of a circuit consists of a Th�v�nin voltage source in series with a Th�v�nin resistor and is valid for any load. In AC circuits a Th�v�nin equivalent circuit is valid for a single frequency.  The Th�v�nin voltage is the open circuit voltage at the output. calculation is straightforward node or loop circuit analysis. Using loop analysis: Voc:  [8 * I1] + [(8+2+6) * I2] - [6 * I3] = 1 A I2 = �A ==> Voc = �A * 6 W = 3 V = Vth Calculate the Th�v�nin resistance from the open circuit voltage and the short circuit current (set RL = 0 and solve for I3) using Ohm's Law. Rth = Voc / Isc = 3 V / [(4/9) A] = 27 / 4 W = Rth

 CURRENT CONVERSIONS Standard unit = Ampere (A)
 abampere ampere statampere 1 abA = 1 10 2.998 * 1010 1 A = 0.1 1 2.998 * 109 1 statA = 3.336 * 10-11 3.336 * 10-10 1

 POTENTIAL CONVERSIONS Standard unit = Volt (V)
 abvolt volt statvolt 1 abV = 1 10-8 3.336 * 10-11 1 V = 108 1 3.336 * 10-3 1 statV = 2.998 * 1010 299.8 1