Question

If the electric field and the magnetic field are equal in magnitude and perpendicular to each other, then:

• A. The current in the circuit is zero \( I = 0 \)
• B. The internal resistance of the cell is zero \( r = 0 \)
• C. Both (A) and (B)
• D. None of these

Hint:

When the electric and magnetic fields are equal and perpendicular, it results in zero current due to the cancellation of forces, and the internal resistance must be zero to maintain no loss of energy.

Answer 1

The Correct Option is C

In the case where both the electric field and the magnetic field are equal in magnitude and perpendicular to each other, the situation generally describes a static or equilibrium condition in a conductor or circuit. 1. If the electric and magnetic fields are equal and perpendicular to each other, the force exerted by the electric and magnetic fields cancels out the net movement of charges in the conductor, resulting in zero current. 2. If the internal resistance \( r = 0 \), the potential difference and current are directly related, but in this specific case, the balance of fields implies no current flow. Thus, both conditions (A) and (B) are correct.