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Electromagnetic Induction — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsElectromagnetic Induction1 Mark
Question
A rod of legth l rotates with a uniform angular velocity $\omega$ about its perpendicular bisector. A uniform magnetic field B exists parallel to the axis of rotation. The potential difference between the two ends of the rod is:
  1. $\text{zero}$
  2. $\frac{1}{2}\text{Bl}\omega^2$
  3. $\text{Bl}\omega ^2$
  4. $2\text{B}\text{l}\omega^2$ 
✓

Answer

  1. $\text{zero}$

Explanation:

Emf at both end is same $=\frac{1}{8}\text{Bwl}^2$

So the potential difference between the two ends of therod is zero.

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