Which of the following is wrong statement - Vidyadip

MCQ

Which of the following is wrong statement

A
An emf can be induced between the ends of a straight conductor by moving it through a uniform magnetic field
✓
The self induced emf produced by changing current in a coil always tends to decrease the current
C
Inserting an iron core in a coil increases its coefficient of self induction
D
According to Lenz's law, the direction of the induced current is such that it opposes the flux change that causes it

✓

Answer

Correct option: B.

The self induced emf produced by changing current in a coil always tends to decrease the current

b
If we more a conductor in a region of magnetic field, an emf is induced into it resulting a flow of current. So option $A$ is right. Accooding to lenz's law, emf is induced in such a way that it opposes the cause producing it not always tends to decrease the current. so option $B$ is cosong.

Since $L \propto$ number of magnelic field lines

$i \propto u$

So, $l$ increases if $u_r$ increase, $l=$ self Inductance

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