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The answer is (b) When the current flows through an inductor. it sets up a ,_ magnetic flux through its coils. When the current changes. 1
the flux changes. Faradag's and Lenz’s Laws tell us that a W—
self-induced emf wilt be created that opposes the change. : 'a' is not true. To establish a current through an inductor, the voltage source has
to do work against the selfrinduced emf. The opposite statement is true. 'b’ is true. The work done by the voltage source to establish the current through
the inductor is stored as magnetic energy in the ﬁeld of the inductor. *c’ is not true. After the circuit is switched off, the ﬂux within the inductor
produces an emf opposing the change, leading to a current that dissipates as the
energy stored within the inductor depletes itself. 'd’ is not true. Substituting "capacitor plates" for "inductor coils“ makes the
statement true. CARhCITﬂRS STCIRE ENERGY I|I'r'HEli'i WCIRH I5 DCiHE TCI MID'III'E CHARGES AEAIHSTAH ELECTRIC FIELEI.
iHEILICTCiRS STURE ElilEFI‘JIi"!I I|I'II"I'IEI'il WCIRH IE DUNE 1-4;. MCWE CI'MRCES AGMHST AMENEI'IC FIELD. © £3395 .J WHEEL ...
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- Spring '11