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Question
Choose the correct option
A current through a coil of self-inductance 10 mH increases from 0 to 1 A in 0.1 s. What is the induced emf in the coil?
Options
0.1 V
1 V
10 V
0.01 V
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Solution
0.1 V
Explanation:
Step 1:
Let e = the induced emf in the coil
Substitute the given values from Question,
Let, self-inductance = L
Change in current = dI
Change in time = dt
`L = 10 mH` .....(1)
`dI = 1 - 0`
= 1A ......(2)
`dt = 0.1s` .....(3)
Applying the concept of Self Inductance or Inductance of the coil.
We get, e =`L (dI)/(dt)` .....(4)
Step 2:
Substitute from (1), (2), (3) and (4) and calculate:
e = `L (dI)/(dt)`
e =`10 xx 10^-3 xx 1/0.1`
e = `0.1v`
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