Search results
Results from the WOW.Com Content Network
When calculating a Thévenin-equivalent voltage, the voltage divider principle is often useful, by declaring one terminal to be V out and the other terminal to be at the ground point. The Thévenin-equivalent resistance R Th is the resistance measured across points A and B "looking back" into the circuit. The resistance is measured after ...
Since the ladder is a series circuit, the current is the same throughout, and is given by the total voltage divided by the total series resistance (V/R eq). The voltage drop across any one resistor is I×R n, where I is the current calculated above, and R n is the resistance of the resistor in question.
Parallel resistance is illustrated by the circulatory system. Each organ is supplied by an artery that branches off the aorta. The total resistance of this parallel arrangement is expressed by the following equation: 1/R total = 1/R a + 1/R b + ... + 1/R n. R a, R b, and R n are the resistances of the renal, hepatic, and other arteries ...
The Norton resistance R no is found by calculating the output voltage V o produced at A and B with no resistance or load connected to, then R no = V o / I no; equivalently, this is the resistance between the terminals with all (independent) voltage sources short-circuited and independent current sources open-circuited (i.e., each independent ...
Figure 4. These circuits are equivalent: (A) A resistor at nonzero temperature with internal thermal noise; (B) Its Thévenin equivalent circuit: a noiseless resistor in series with a noise voltage source; (C) Its Norton equivalent circuit: a noiseless resistance in parallel with a noise current source.
At each stage, resistors for the "rung" and "leg" are chosen so that the rung value matches the leg value plus the equivalent resistance of the previous rungs. The rung and leg resistors can be formed by pairing other resistors in series or parallel in order to increase the number of available combinations. This process can be automated.
These include resistors in series, resistors in parallel and the extension to series and parallel circuits for capacitors, inductors and general impedances. Also well known are the Norton and Thévenin equivalent current generator and voltage generator circuits respectively, as is the Y-Δ transform. None of these are discussed in detail here ...
Summarizing, for any truly ohmic device having resistance R, V/I = ΔV/ΔI = R for any applied voltage or current or for the difference between any set of applied voltages or currents. The I–V curves of four devices: Two resistors, a diode, and a battery. The two resistors follow Ohm's law: The plot is a straight line through the origin.