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Question
An emf of 91 mV is induced in the windings of a coil when the current in o nearby coil is increasing at the rate of 1.3 A/s. what is the mutual inductance (M) of the two coils in mH?
Solution
Given,
es = 91 mv = 91 × 10-3 V
`("dl"_"P")/"dt"` = 1.3 A/S
M = ?
Induced emf in the coil is
`"e"_"s" = "M" ("dl"_"P")/"dt"`
M = `"e"_"s"/(("dl"_"P"//"dt"))`
`= (91 xx 10^-3)/1.3`
= 70 × 10-3 H
M = 70 mH
Mutual inductance of two coil is 70 mH.
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