Question

Magnetic field due to current carrying conductor depends on:

• A. Current flowing through the conductor
• B. Distance from the conductor
• C. Length of the conductor
• D. (a) and (b)

Answer 1

The correct option is D

(a) and (b)

Explanation for correct option:

1. The magnetic field is generated by a current-carrying conductor.
2. The magnetic field due to a current element is given by Biot-Savart's law.
3. According to this law, the magnetic field at any point due to a current element $Id\overrightarrow{l}$ is given by
   $d\overrightarrow{B}=\frac{{\mu }_0}{4\mathrm{\pi }}\frac{Id\overrightarrow{l}\times \overrightarrow{R}}{R^3}$
   Where $\overrightarrow{R}$ is the vector from the current element to the point of observation and the constant ${\mu }_0=4\mathrm{\pi }\times {10}^{-7}\mathrm{N}/{\mathrm{A}}^2$ is called the permeability of free space,
4. From Biot-Savart's law, we can see that the magnetic field due to the current-carrying conductor depends on the current $Id\overrightarrow{l}$ flowing through the conductor.
5. From Biot-Savart's law, we can see that the magnetic field due to the current-carrying conductor depends on the distance $\overrightarrow{R}$ from the conductor.
6. Hence, both (a) and (b) are the correct options.

Therefore, the correct answer is option (D).