Two concentric circular loops lie in the same plane with a common centre

PHYSICS · Multi-part · CBSE · Physics · Moving Charges and Magnetism · Moving Charges and Magnetism

Problem

Two concentric circular loops lie in the same plane with a common centre. The larger loop has radius

10\,\text{cm}

and carries a current of

6\,\text{A}

clockwise. The smaller loop has radius

5\,\text{cm}

and carries a current

I

anticlockwise. (i) Write separate expressions for the magnitudes of the magnetic fields at the common centre due to each loop in terms of the given quantities. (ii) Derive an expression for the magnitude of the net magnetic field at the centre in terms of

I

. (iii) Calculate the value of

I

required so that the net magnetic field at the centre is zero. (iv) If the current in the smaller loop is doubled from the value found in part (iii) while the current in the larger loop remains

6\,\text{A}

, state the direction of the net magnetic field at the centre and calculate its magnitude.

Related theory

Browse the problem library