A wire 0.2 m long carries 10 A at right angles to a magnetic field of 2 T. What force acts on it?
Answer and explanation
Correct answer: C. 4 N
- Step 1: F = BIL sin θ, with sin 90° = 1. Step 2. F = 2 × 10 × 0.2 = 4 N. Answer: 4 N. Why not the others: 20 N is what you get if you forget the length. 1 N is what you get if you divide by B. 40 N is what you get if you misplace a power of ten.
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