ELECTRONIC PRINCIPLES - OD1647 - LESSON 1/TASK 1
FIGURE 20. GROWTH AND DECAY OF CURRENT IN AN LR SERIES CIRCUIT.
Electrical inductance is like mechanical inertia, and the growth
of current in an inductive circuit can be likened to the
acceleration of a boat on the surface of water. The boat does
not move at the instant a constant force is applied to it. At
this instant, all the applied force is used to overcome the
inertia of the boat. Once the inertia is overcome, the boat
will start to move. After a while, the speed of the boat
reaches its maximum value, and the applied force is only used in
overcoming the friction of the water against the hull.
When the battery switch (S1) in the LR circuit of figure 20, view
A, is closed, the rate of current increase is maximum in the
inductive circuit. At this instant, all the battery voltage is