Question

State Biot-Savart's law and write it in vector form.

Answer 1

Solution :

(i) |dB−→|=μ04πI|dl→×r→|r3

or dB−→=μ04πIdl→×r→r3

The direction of dB−→ is the direction of the vector dl→×r→ .

It is given by right hand screw rule.

If we place a right handed screw at a point perpendicular to the plane of paper and turn it handle from dl→ to r→ , then the direction in which the screw advance given direction dB−→