A current of 0.1 A circulates around a coil of 100 turns and having a radius equal to 5 cm. The magnetic field set up at the centre of the coil is (μο = 4π × 10⁻⁷ weber/ampere-metre) A 4π × 10⁻⁵ tesla B 8π x 10⁻⁵ tesla C 4 x 10⁻⁵tesla D 2 x 10⁻⁵ tesla
