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An aircraft has a wing span of 36 m. It flies horizontally at 250 m/s…
Contributed by StemPy LabTry it on paper first. A hint, the key idea and the worked solution are here when you need them.
An aircraft has a wing span of m. It flies horizontally at m/s. At that place the vertical part of the field of the Earth is T. What is the emf between the wing tips? What is it if the aircraft flies at half the speed?
Need a reminder? The key ideaShow
A rod of length that moves at speed at right angles to the field has . On rails with a total resistance , , the force on the rod is , and the power is . A tilted field counts only by its part at right angles to the rod and to its velocity. A rod that turns about one end has .
The worked solution
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. The emf. .
Step 2. Half the speed. The emf goes as , so it halves to V.
Answer: V, and V.
Watch out. The horizontal part of the field is along the direction of flight in some places, and it does not add to the emf of a horizontal wing. Only the part at right angles to both the wing and the velocity counts.
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