Question

Given below are two statements :
Statement I : Biot-Savart's law gives us the expression for the magnetic field strength of an infinitesimal current element (IdI) of a current carrying conductor only.
Statement II : Biot-Savart's law is analogous to Coulomb's inverse square law of charge $q$, with the former being related to the field produced by a scalar source, Idl while the latter being produced by a vector source, $q$.
In light of above statements choose the most appropriate answer from the options given below:

• A. Statement I is incorrect and Statement II is correct
• B. Both Statement I and Statement II are correct
• C. Both Statement I and Statement II are incorrect
• D. Statement I is correct and Statement II is incorrect

Answer 1

Answer: (D)

$dB=\frac{{\mu }_0(Id\vec{\ell }\times \vec{r})}{4\pi r^3}$
As per Biot Savart law, the expression for magnetic field depends on current carrying element $Id\vec{\ell }$, which is a vector quantity, therefore, statement-I is correct and statement-II is wrong.