Two circuits are dual if the mesh equations that characterize one of them have the same mathematical form as nodal equations that characterize the other

A current-carrying conductor produced a magnetic field (1800). A changing magnetic field could induce a voltage in a neighboring circuit(1820)

The voltage follower is a circuit in which the output is identical to the input

The operational amplifier (hereafter OP-AMP)is developed in the 1940s primarily for use in analog computers, made cheaply and readily available in the late 1960s through integrated-circuit technology. The actual construction of a modern OP-AMP is indeed very complex, involving many transistors, diodes, resistors and capacitors

One of the main uses of Thevenin's and Norton's theorems is the replacement of a large part of network very simple equivalent

Mesh analysis is applicable only to those networks, which are planar. If it is possible to draw the diagram of a circuit on a plane surface in such a way that no branch passes over or under any other branch, then that circuit is said to be planar circuit. (Non-planar-circuit

The voltage division The current division

Any given arm of the Y network is found by taking the product of the two adjacent arms of the network and dividing by the sum of the network arms

A point at which two or more elements have common connection is called node(节点). Suppose that we start at one node in a network and move through a simple element to the node at the other..., if no node was encountered more than once, then the set of nodes and elements that we have passed hrough is defined as path(路径)

81-1 Introduction 1 Circuit models(模型) The voltage source Two active(有源) models The current source The resistor Three passive无源) models The inductor The capacitor