Home
Class 12
PHYSICS
A very long straight wire of radius r ca...

A very long straight wire of radius r carries current I. Intensity of magnetic field B at point lying at a perpendicular distance 'a' from the axis is `alpha` ______ . (where `altr`)

A

`a^(2)`

B

`(1)/(a^(2))`

C

`(1)/(a)`

D

a

Text Solution

Verified by Experts

The correct Answer is:
D

`B xx 2pia= mu_(0) xx (I)/(pir^(2))xx pia^(2)`
`B= (mu_(0)I)/(2pir^(2))a`
`B prop a`
Promotional Banner

Similar Questions

Explore conceptually related problems

An extremely long straight wire, with radius of cross-section a, carries current I. Then ratio of magnetic fields at distances a/2 and 2a from its axis would be ______ .

A long straight wire carries a current of 35 A. What is the magnitude of the field B at a point 20 cm from the wire?

A long straight wire carries a current of 35 A. What is the magnitude of the field B at a point 35 cm from the wire ?

Write formula of the magnetic field at r perpendicular distance for finite current carrying wire.

A long straight solid metal wire of radius R carries a current I, uniformly distributed over its circular cross-section. Find the magnetic field at a distance r from axis of wire (i) inside and (ii) outside the wire.

A small circular flexible loop of wire of radius r carries a current I. It is placed in a uniform magnetic field B. The tension in the loop will be doubled if ______ .

A current of 1 ampere is passed through a straight wire of length 2.0 meters. What value of magnetic field at a point in air at a distance of 3 meters from either end of wire and on the axis of wire ?

At a distance of 10 cm from a long straight wire carrying current, the magnetic field is 0.04 T. At the distance of 40 cm, the magnetic field will be ______ .

For a circular coil of radius R and N turns carrying current. Prove that the magnitude of the magnetic field at a point on its axis at a distance X from its centre is given by B=(mu_0IR^2N)/(2(x^2+R^2)^(3//2))