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An aircraft of wingspan 40 m flies eastward at 1080 km/h at constant altitude in the northern hemisphere, where the vertical component of Earth's magnetic field is 1.75 * 10⁻⁵ T. What emf is developed between the wing tips?
- 0.21 V
- 2.1 V
- 0.021 V
- 21 V
Correct answer: 0.21 V
Solution
Only the vertical component of B cuts across the horizontal wings as the plane moves horizontally. With v = 300 m/s, emf = 1.75*10⁻⁵ * 40 * 300 = 0.21 V.
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