Magnetic field strength at the centre of regular pentagon made of a conducting wire of uniform cross section area as shown in figure is:

the position vector of the centre of mass lt to r cm of an asymmetric uniform bar of negligible area of cross - section as shown in figure is :

the position vector of the centre of mass lt to r cm of an asymmetric uniform bar of negligible area of cross - section as shown in figure is :

The magnetic field strength at a point P distant r due to an infinite straight wire carrying a current i is as shown in the figure

The magnetic field strength at a point P distant r due to an infinite straight wire carrying a current i is as shown in the figure

A square loop of length L is made of wire of uniform cross-section carrying current l as shown in figure then magnetic field at centre of square is

Assertion : If a current is flowing through a conducting wire of non-uniform cross-section, drift speed and resistance both will increase at a section where cross-sectional area is less. Reason : Current density at such sections is more where cross-sectional area is less.

Assertion : If a current is flowing through a conducting wire of non-uniform cross-section, drift speed and resistance both will increase at a section where cross-sectional area is less. Reason : Current density at such sections is more where cross-sectional area is less.

A circular loop of radius 'r' of conducting wire connected with a Voltage source of zero internal resistance produces a magnetic field 'B' at its centre. If instead, a circular loop of radius '2r' made of same material, having the same cross section is connected to the same voltage source, what will be the magnetic field at its centre?

A circular loop of radius 'r' of conducting wire connected with a Voltage source of zero internal resistance produces a magnetic field 'B' at its centre. If instead, a circular loop of radius '2r' made of same material, having the same cross section is connected to the same voltage source, what will be the magnetic field at its centre?

Why should the area of cross section of metre bridge wire be uniform?