A circular loop of radius R is carrying current i A . The ratio of magnetic field at the centre of circular loop and at a distance R from the center of the loop on its axis is :

Step-by-step solution

The magnitude of magnetic field at the centre of loop is B 1  = B centre  = μ ∘ i 2 R                       … 1 The magnitude of magnetic field at a point at a distance x from the centre along axis of loop is B axis  = μ ∘ i R 2 2 R 2 + x 2 3 2   B 2  = μ ∘ i R 2 2 2 3 2 R 3                     … 2 ( since   x = R ) Dividing equation 1 by