JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
In a co-axial straight cable, the central conductor and the outer conductor carry equal currents in opposite directions. _______ The magnetic field is zero.
- A inside the outer conductor
- B in between the two conductors
- C outside the cable
- D inside the inner conductor
Answer & Solution
Correct Answer
(C) outside the cable
Step-by-step Solution
Detailed explanation
\(\oint \overrightarrow{\mathrm{B}} \cdot \overrightarrow{\mathrm{d} \ell}=\mu_0 \mathrm{i}_{\mathrm{enc}}=0\) \(\dot{\triangle} \mathrm{B}=0\) outside the cable
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