JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
Two long current carrying conductors are placed parallel to each other at a distance of \(8 \,cm\) between them. The magnitude of magnetic field produced at mid-point between the two conductors due to current flowing in them is \(300 \,\mu T\). The equal current flowing in the two conductors is ...............
- A \(30 \,A\) in the same direction
- B \(30 \,A\) in the opposite direction
- C \(60 \,A\) in the opposite direction
- D \(300 \,A\) in the opposite direction
Answer & Solution
Correct Answer
(B) \(30 \,A\) in the opposite direction
Step-by-step Solution
Detailed explanation
\(B\) at \(O =2 \frac{\mu_{0} I }{2 \pi r }\) \(\frac{2 \times 4 \pi \times 10^{-7} I }{2 \pi 4 \times 10^{-2}}=3 \times 10^{-4} T\) \(I =30\, A\) in opp. direction
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