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When the key is closed, a spark is gener...

When the key is closed, a spark is generated between the ends of the rods.

a. Explain the cause of the spark.
b. Explain why a spark is also produced when the key is opened.
c. Why are no sparks produced when the key is left closed?

Text Solution

Verified by Experts

a. The induced e.m.f is secondary
b. During decay actually a large e.m.f should be induced in the secondary
c. No variation of flux takes place
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