Concepts Of Physics MCQ Edition [Volume 2]PhysicsElectromagnetic Induction
A conducting rod having length vector l travels with a constant velocity v in a magnetic field B . A potential difference develops across its two ends
Options
- Aif ( v B ) l 0
- Bif l B
- Cif v B
- Dif v l
Correct answer
A. if ( v B ) l 0
Step-by-step solution
The motional electromotive force (EMF) induced across the ends of a conducting rod of length vector l moving with velocity v in a magnetic field B is given by the scalar triple product of these three vectors. e = ( v B ) l For a potential difference to develop across the ends of the rod, the induced EMF must be non-zero. e 0 ( v B ) l 0 If l B , v B , or v l , the scalar triple product becomes zero, and no potential difference is developed.