Search results
Results from the WOW.Com Content Network
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 ...
It is constructed from four resistors, two of known values R 1 and R 3 (see diagram), one whose resistance is to be determined R x, and one which is variable and calibrated R 2. Two opposite vertices are connected to a source of electric current, such as a battery, and a galvanometer is connected across the other two vertices. The variable ...
The equivalent resistance R th is the resistance that the circuit between terminals A and B would have if all ideal voltage sources in the circuit were replaced by a short circuit and all ideal current sources were replaced by an open circuit (i.e., the sources are set to provide zero voltages and currents).
This circuit does not have a resistor like the above, but all tuned circuits have some resistance, causing them to function as an RLC circuit. An RLC circuit is an electrical circuit consisting of a resistor (R), an inductor (L), and a capacitor (C), connected in series or in parallel. The name of the circuit is derived from the letters that ...
A general formula for the current I X in a resistor R X that is in parallel with a combination of other resistors of total resistance R T (see Figure 1) is [1] = +, where I T is the total current entering the combined network of R X in parallel with R T.
This is equivalent to calculating the Thevenin resistance. When there are dependent sources, the more general method must be used. The voltage at the terminals is calculated for an injection of a 1 ampere test current at the terminals. This voltage divided by the 1 A current is the Norton impedance R no (in ohms). This method must be used if ...
For example, a 10 ohm resistor connected in parallel with a 5 ohm resistor and a 15 ohm resistor produces 1 / 1/10 + 1/5 + 1/15 ohms of resistance, or 30 / 11 = 2.727 ohms. A resistor network that is a combination of parallel and series connections can be broken up into smaller parts that are either one or the other.
For a simple two-terminal device, the small signal equivalent circuit may be no more than two components. A resistance equal to the slope of the v/i curve at the operating point (called the dynamic resistance), and tangent to the curve. A generator, because this tangent will not, in general, pass through the origin.