Q. 23.9( 36 Votes )

# 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?

Answer :

Given:

Current through the wire, I = 35 A

Distance of point P from the wire, d = 20 cm

Using Biot Savart law we can find magnetic field at a distance d from a current carrying conductor.

It is given by:

…(1)

Where,

B = Magnetic field strength

I = current through the coil

�_{0} is the permeability of free space.

�_{0} = 4 × π × 10^{-7} TmA^{-1}

d = distance of point P

By plugging the values in the equation (1), we get

⇒

⇒ |B| = 3.5 × 10^{-5}T

In this case the magnetic field at 20 cm away from a current carrying conductor is found to be 3.5 × 10^{-5}T.

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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?

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