COMEDK · Physics · 21. Magnetic Effects of Current
Current flows through uniform, square frames and their connecting wires as shown in the figure. In which case is the net magnetic field at the centre of the frame not zero?
- A B
- B A
- C D
- D C
Answer & Solution
Correct Answer
(D) C
Step-by-step Solution
Detailed explanation
The square frame itself always produces zero net field at the centre (symmetric current paths cancel). Cases A and B: External wires are directed radially (along diagonals) toward/away from the centre \(\Rightarrow\) their line of action passes through the centre, so they…
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