Explain with the help of a labelled diagram the underlying principle and working of a step-up transformer. Why cannot such a device be used to step-up d.c. voltage?
CBSE DELHI - SET 1 2007
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Principle: When alternating current flows through the primary, the magnetic flux linked with the secondary changes. As a result, an e.m.f. is induced in it.
Alternate Answer
It works on the principle of Mutual Induction.
Working: Change of flux is zero for d.c.
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