Currents through ABC and `A^'B^'C^'` is I, figure. What is the magnetic field at P? `BP=PB^'=r`. (Here `C^'B^'PBC` are collinear)

Current through ABC and A'B'C' is 1. What is the magnetic field at P? BP = PB' = r (Here C'B'PBC are collinear)

Find the magnetic field B at the point P in figure

Find the magnetic field B at the point P in figure

Current I is flowing through a circular coil of radius r. It is placed in a magnetic field B in such a way that the plane of the circular coil is perpendicular to B. The force acting on it will be -

A circular coil 'A' has a radius R and the current flowing through it is I.Another circular coil 'B' has a radius 2R and if 2I is the current flowing through it then the magnetic fields at the centre of the circular coil are in the ratio of