NEET 2023 Phase 2 · PhysicsForce on wirePrevious Year Question
A long straight wire of length 2 m and mass 250 g is suspended horizontally in a uniform horizontal magnetic field of 0.7 T. The amount of current flowing through the wire will be (g = 9.8 m s⁻²)
Answer: (B) 1.75 A. Answer: (B) Solution: For the wire to remain suspended, the magnetic force balances gravity: B I L = m g.
- A.2.75 A
- B.1.75 A✓
- C.2.45 A
- D.2.25 A
Correct Answer
(B) 1.75 A
Solution & Explanation
Answer: (B) Solution: For the wire to remain suspended, the magnetic force balances gravity: B I L = m g. I = m g / (B L) = (0.250 × 9.8) / (0.7 × 2) I = 2.45 / 1.4 = 1.75 A.
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