List of top Physics Questions on Magnetic Field asked in CBSE CLASS XII

Four long straight thin wires are held vertically at the corners A, B, C and D of a square of side \( a \), kept on a table and carry equal current \( I \). The wire at A carries current in upward direction whereas the current in the remaining wires flows in downward direction. The net magnetic field at the centre of the square will have the magnitude:

Considering the case of magnetic field produced by air-filled current carrying solenoid, show that the magnetic energy density of a magnetic field \( B \) is \( \frac{B^2}{2\mu_0} \).

Using Biot-Savart law, derive expression for the magnetic field \( \vec{B} \) due to a circular current carrying loop at a point on its axis and hence at its center.