A steady current is set up in a cubic network composed of wires of equal resistance and length as shown. What is the magnetic field at the centre P due to the cubic network?
Show Hint
Highly symmetric current distributions often lead to zero net magnetic field at the centre.
Step 1: Analyzing symmetry of the cube.
Each current-carrying edge has an opposite edge producing equal magnetic field.
Step 2: Superposition principle.
Magnetic fields due to opposite sides cancel each other at the centre.
Step 3: Net magnetic field.
The resultant magnetic field at point P is zero.