ELECTRONIC PRINCIPLES - OD1647 - LESSON 1/TASK 1
low. Conversely, if the coils are close together so that nearly
all the flux of one coil links the turns of the other, the
increased greatly by mounting the coils on a common iron core.
FIGURE 22. THE EFFECT OF POSITION OF COILS ON MUTUAL
INDUCTANCE.
Two coils are placed close together as shown in figure 23 on the
following page. Coil I is connected to a battery through switch
S, and coil 2 is connected to an ammeter (A). When switch S is
closed, as in figure 23, view A, the current that flows in coil
induced voltage in coil 2 and a momentary deflection of the
ammeter. When the current in coil 1 reaches a steady value, the
ammeter returns to zero. If switch S is now opened as in figure
23, view B, the ammeter (A) deflects momentarily in the opposite
direction, indicating a momentary flow of current in the
opposite direction
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