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GUJCET · Physics · Moving Charges and Magnetism
A very long straight wire of radius \(r\) carries current I. Intensity of magnetic field B at a point, lying at a perpendicular distance ' \(a\) ' from the axis is ________ (Where a < r ).
- A \(a^2\)
- B \(\frac{1}{a^2}\)
- C \(\frac{1}{a}\)
- D \(a\)
Answer & Solution
Correct Answer
(D) \(a\)
Step-by-step Solution
Detailed explanation
D
Magnetic field inside a wire is given by
\(B=\frac{\mu_0 i a}{2 \pi r^2}=B \alpha a\)
Magnetic field inside a wire is given by
\(B=\frac{\mu_0 i a}{2 \pi r^2}=B \alpha a\)
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