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Class 12
Physics
Moving Charges and Magnetism
a long straight wire carries a current of 35 a wh...

Question:
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:

Current in the wire, I = 35 A

Distance of a point from the wire, r = 20 cm = 0.2 m

Magnitude of the magnetic field at this point is given as:

Where,

μ₀= Permeability of free space = 4π × 10^â€“7 T m A^â€“1

Hence, the magnitude of the magnetic field at a point 20 cm from the wire is 3.5 × 10^â€“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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Question:
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?