Page 91 - Basic Electrical Engineering
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This work done is stored in the electrostatic field set up between the plates of
the capacitor in the form of energy. Thus, the energy stored, E is expressed as
Example 1.17 The current through a 100 mH inductor charges from 0 to
200 mA in 4 µs. What is the value of the induced EMF in the inductor or the
choke?
Solution:
It is observed that a high voltage is induced in the choke because of very fast
change of current flow through it. In a tube light circuit, a high voltage is
induced in the choke by the same method and is used to ionize the gas inside
the tube light, and thus start the tube light.
Example 1.18 Self inductances of two coils are L = 2 H and L = 8 H. The
2
1
coil L produces a magnetic flux of 80 mWb of which only 60 µWb are
1
linked with coil L . Calculate the mutual inductance of the two coils.
2
