To the electric circuit which resembles balanced bridge one ( the branch of the balanced bridge connected with voltage source in series or connected with current source in parallel), we can use reciprocal theorem to reason out some simple solutions that use the character of balanced bridge to solve such problems.

Simulated bio-environmental data communication system and application of reciprocity theorem;

As a result , a distinct method to prove the reciprocity theorem is obtained.

Expressions of the coupling length and the coupling area of an antenna to electromagnetic waves excitation are deduced with the reciprocity theorem.

This article gives a description of a method to ascertain the magnetic field at any arbitrary point of magnetic dipole space by a kind of reciprocity principle.

We treat magnetic dipoles as circulation equivalently,apply the reciprocity principle,and give a method of the spatial distribution of a magnetic field.

The reciprocal theorem is used to make research on the bending of a set square with free hypotenuse under a concentrated load acting at any of its points, and its accurate solution is given.

But the energy principles in dynamic theory of piezoelectric materials with voids, which the principle of virtual work, the reciprocal theorem and various variational principles are not yet established systematic.

Based on this relation, it is possible not only to obtain the principle of virtual work and the reciprocal theorem in dyn.