A coil having N turns is wound tightly in the form of a spiral with inner and outer radii a and b respectively. When a current I passes through the coil, the magnetic field at the centre is
As we learnt in
Magnetic Field due to Circular Current at the centre -
If a coil of radius r is carrying current i then magnetic feild at a distnace X from its centre is:
- wherein
Consider a small thickness dx at distance x from centre.
Number of turn in
Option 1)
incorrect
Option 2)
incorrect
Option 3)
correct
Option 4)
incorrect