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2 Basic Electromagnetism
Suppose that there is an electron travelling in a conductor. The electron tends to
move in the normal direction to the propagation direction in the conductor due to the
Lorentz force. In practice, however, the electron moves along the conductor. This is
caused by the Coulomb force of cations (and if the Hall effect is appreciable, the
influence of the distributed Hall electrons is also included). That is, the transverse
movement of the traveling electron is strongly suppressed by the cations. This means
that a reaction, which is also the Coulomb force, is exerted on the cations. Hence, this
reaction pushes the conductor in the direction of the Lorentz force. Thus, a Coulomb
force of the same strength as the Lorentz force is exerted on the conductor. Hence,
the statement that the Lorentz force moves the conductor is not correct.
In fact, the Coulomb force moves the conductor, and it is false to think that the
Lorentz force moves it. The Coulomb force is not responsible for this, however,
but the origin of this movement is electric power source. An electromotive force is
induced when the conductor is forced to move, and the electromotive force works to
stop the motion of the conductor. That is, if the work done by the electromotive force
is realized, it cancels out the mechanical work that causes a loss energy. Nevertheless,
the electric power source supplies additional energy to the circuit to keep the current
constant. This causes the loss energy.
Someone is walking while revolving a ball by pulling a string connected to the
ball. Assume that the ball approaches an object and the object falls down due to
the wind produced by the moving ball and is damaged. The force that destroyed the
object is the wind pressure, but it is not the centripetal force, i.e., the line tension of
the string. The responsibility for the destruction lies with the person who revolved
the ball and added a force to prevent the ball from slowing down by the reaction of
the wind pressure. If he would not have added the force, the speed of the ball might
have been reduced and the object might not have fallen down.
Then, what is the case of the Lorentz force that works on quantized flux lines
when a current is applied to a superconductor in a magnetic field? It is assumed that
the superconductor is fixed so as not to move.
2 Basic Electromagnetism
Suppose that there is an electron travelling in a conductor. The electron tends to
move in the normal direction to the propagation direction in the conductor due to the
Lorentz force. In practice, however, the electron moves along the conductor. This is
caused by the Coulomb force of cations (and if the Hall effect is appreciable, the
influence of the distributed Hall electrons is also included). That is, the transverse
movement of the traveling electron is strongly suppressed by the cations. This means
that a reaction, which is also the Coulomb force, is exerted on the cations. Hence, this
reaction pushes the conductor in the direction of the Lorentz force. Thus, a Coulomb
force of the same strength as the Lorentz force is exerted on the conductor. Hence,
the statement that the Lorentz force moves the conductor is not correct.
In fact, the Coulomb force moves the conductor, and it is false to think that the
Lorentz force moves it. The Coulomb force is not responsible for this, however,
but the origin of this movement is electric power source. An electromotive force is
induced when the conductor is forced to move, and the electromotive force works to
stop the motion of the conductor. That is, if the work done by the electromotive force
is realized, it cancels out the mechanical work that causes a loss energy. Nevertheless,
the electric power source supplies additional energy to the circuit to keep the current
constant. This causes the loss energy.
Someone is walking while revolving a ball by pulling a string connected to the
ball. Assume that the ball approaches an object and the object falls down due to
the wind produced by the moving ball and is damaged. The force that destroyed the
object is the wind pressure, but it is not the centripetal force, i.e., the line tension of
the string. The responsibility for the destruction lies with the person who revolved
the ball and added a force to prevent the ball from slowing down by the reaction of
the wind pressure. If he would not have added the force, the speed of the ball might
have been reduced and the object might not have fallen down.
Then, what is the case of the Lorentz force that works on quantized flux lines
when a current is applied to a superconductor in a magnetic field? It is assumed that
the superconductor is fixed so as not to move.