An aircraft with a 10m wingspan flies from the equator toward the North Pole, wings orthogonal to the Earth's vertical magnetic field component (B = 4×10-5T). At peak velocity, a 96mV EMF is induced across wingtips. The maximum aircraft speed is____________?
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Answer: B. 384msec-1
Explanation
Induced electromotive force equals magnetic field multiplied by wingspan and aircraft velocity. Substituting the given wingspan, magnetic field, and EMF values allows solving for maximum speed. Algebraic rearrangement and calculation yields a maximum aircraft speed of three hundred eighty four meters per second. Faraday law applies to aircraft cutting through vertical components of Earth magnetic field lines. Wings orthogonal to magnetic fields maximize the induced voltage across the aircraft wingtips. Converting all parameters to standard SI units ensures correct calculation of speed in meters per second.
Aviation instrumentation must account for induced electrical potentials across metal airframes during flight. Geomagnetic field measurements help researchers study Earth core dynamics and magnetospheric interactions. Calculating motional emf is a classic physics problem demonstrating electromagnetic induction principles. Option A is wrong because one hundred fifty meters per second produces a much smaller induced EMF. Option C is incorrect because misplaced decimal points result in incorrect velocity magnitude values. Option D is wrong because two hundred meters per second does not satisfy the induction equation here.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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