JEE Mains · Physics · STD 12 -6. Electromagnetic induction
A metallic rod of length ' \(L\) ' is rotated with an angular speed of ' \(\omega\) ' normal to a uniform magnetic field ' \(B\) ' about an axis passing through one end of rod as shown in figure. The induced emf will be :
- A \(\frac{1}{4} B ^2 L \omega\)
- B \(\frac{1}{4} BL ^2 \omega\)
- C \(\frac{1}{2} BL ^2 \omega\)
- D \(\frac{1}{2} B ^2 L ^2 \omega\)
Answer & Solution
Correct Answer
(C) \(\frac{1}{2} BL ^2 \omega\)
Step-by-step Solution
Detailed explanation
\(\int d \varepsilon=\int B (\omega x ) dx\) \(\varepsilon= B \omega \int \limits_0^{ L } x dx =\frac{ B \omega L ^2}{2}\)
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