Q116 / 180 · AIIMS 2011 · Physics

Magnetic field at $a$ distance a from long current carrying wire is proportional to

Correct answer
A
$\frac{1}{a}$
B
$\frac{1}{a^2}$
C
$\frac{1}{\sqrt{a}}$
D
$\frac{1}{a^{3 / 2}}$

Solution

The expression for magnetic field is case of a long current carrying wire is $B=\frac{\mu_0 I}{2 \pi a}$ i.e, $B \propto \frac{1}{a}$

Hence, the correct answer is option: 'A'.

Relevant Questions

Find force per unit length at .26 May, 2019Magnetic Field
The magnetic field inside a long solenoid having turns per unit length and carrying current when iron core is kept in it is ( permeability o26 May, 2019Magnetic Field
Two parallel infinitely long current carrying wires are shown in figure. If resultant magnetic field at point is zero. Then determine curren25 May, 2019Magnetic Field
A long cylindrical wire carrying current of 10 A. has radius of , then find its magnetic field induction at a point from the centre of the w26 May, 2018Magnetic Field
A current is flowing through the loop. The direction of the current and the shape of the loop are as shown in the figure. The magnetic field2017Magnetic Field
The magnetic field at the centre of the arc shown in the figure is2016Magnetic Field