Physics

Problem

A circular coil of 40 turns produces a magnetic field of

800\,\mu\text{T}

at its centre when it carries a current of

5\,\text{A}

. The same length of wire is now rewound to make a coil with 80 turns. The current remains

5\,\text{A}

. What is the new magnetic field at the centre of the coil? a)

1600\,\mu\text{T}

800\,\mu\text{T}

3200\,\mu\text{T}

6400\,\mu\text{T}