In determining the feasibility of a real MAGLEV transportation system, performance will be based upon speed, vehicle cost, and passenger capacity, among other factors. Awards will be distributed based on these and other performance categories.
All else being equal, adding passengers will tend to reduce a vehicle's maximum speed. Passengers add weight. They also make the vehicle larger. Pennies will be used to represent passengers carried by a model vehicle.
All things being equal, increasing a vehicle's carrying capacity will tend to increase cost. A heavy-duty MAGLEV suspension system to support a larger car and the more people will probably cost more than a light-duty system. Vehicle costs will be represented by the number of magnets used in a model vehicle.
The engineer must design a vehicle which carries the most pennies at the fastest speed while using the least amount of magnets. This is how real engineering problems present themselves. The engineer who finds the best compromise is the one who becomes successful.
The engineer will need some way to actually judge which compromise is best. Is a car which goes twice as fast, has half as many magnets and half as many pennies as another car "better" or "worse"?
Ratio performance measures of this sort are very common: price-to-earnings ratio for stocks; miles-per-gallon for cars; price-per-pound for meat, etc. By using them we can compare Apple with IBM, Volkswagens with Hummers, and sirloin with hamburger. Similarly, we can construct an FOM to compare maglev designs with different speeds, capacity and cost:
This can be put in terms of what we will measure. Let the distance between timing points on the track be "X" feet. Let the time to go between the timing points be "T" seconds. Speed (S) = X/T. That gives you (algebra):
For the MAGLEV contest, P, and/or N and/or T may be different for each vehicle. X however will be the same for all vehicles, i.e. the 16' between the timers. To get the FOM, multiply the number of pennies (P) by 16' (X) and divide the result by the number of magnets (N) and again by the measured time (T, in seconds).
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