h a l f b a k e r yIncidentally, why isn't "spacecraft" another word for "interior design"?
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It only takes about 12 horsepower to cruise at about 100kph. It takes 100 horsepower or more to quickly accelerate to cruising speed. So, most wastage of gas is directly related to the desire of the driver to accelerate quickly, and the mass of the car. Lifting some of the weight of the car doesn't affect the mass that must be accelerated, not by one whit. |
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erm, braking and cornering? |
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The French will adopt a south-pole-up configuration,
the English will go for south-pole-down. The
Americans, meanwhile, will put grossly oversized
magnets on the base of the car, allowing them to
use smaller magnets in the road. |
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As a result, cars driven outside their country of
origin will either clamp themselves immovably to
the road, hover uncontrollably above it, or flip over
entirely. |
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Won't help inertia or wind resistance, but
presumably would help frictional losses in the
bearings and from deformation of rubber tires at
the point of contact with the road. At the cost of
handling. So, better arrange the magnets to exert
some horizontal force, as well, to keep the cars in
their lanes. That'll work better if lane-switching is
restricted. In other words, a mag-lev train.
Conjecture: *any* vehicle, in the limit as it's
optimized for efficiency, becomes a train. |
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//flip over entirely// Where's the problem? Just
design invertible cars with gimbal-mounted seats. |
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Whole host of problems here. |
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1. Magnetic repulsive power decreases with the inverse square law, so the car magnets would have to be so close to the road as to be aerodynamically probably a net loss in efficiency. |
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2. Magnets are heavy, I'm not sure how the repulsive force compares with their weight, but I'm sure it's not great. |
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3. F = m*g*mu + œ*rho*Cd*Av^2 + ma + m*g*sin(road angle), where the mgC term becomes (mg-F(magnet))*mu, and m has increased by the mass of the magnets themselves. |
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As [Vernon] implied, and [mp] mentioned, maglev only helps with rolling resistance. Given that rolling resistance is a relatively miniscule portion of automotive energy use, this won't help much. |
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Given the related worsening of braking distance and cornering ability due to lower friction forces, it's a net loss in function. |
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Also, if you run someone over, they'll be glued to
the underside of your car by their belt buckle. |
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Also too, you'd have to stop every few tens of miles
to try to remove the bits of unexpected metal junk
from the underside of your car. (Actually, that
might not be a problem: if the road is also
magnetized, it will tenaciously hold on to nails,
screws and other bits of junk, holding them
conveniently in the driving line.) |
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All of which makes this a great idea for the Halfbakery (+). |
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As soon as you start to decouple a vehicle from frictional contact with its supporting surface, you get massive problems with both propulsion and steering - hovercraft are the classic example, relying entirely on aerodynamic methods. |
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This would convert passenger motor vehicles into little more than unstable, highly dangerous and barely-guided projectiles. |
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Hooooboy. Bad science, bad physics, hideous economics [-] |
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We've gone over and over this one; giving cars lift to save
fuel is not a good idea! There are at least a hundred ways
to make a car more fuel efficient that will _not_ send it
careening into the bushes at the first bend in the highway,
so why still with the lift thing? And as far as that bad idea
goes, this may be the worst variant I've seen yet. |
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Don't give up so easily. This idea deals with dragging the metal around; just combine it with teflon tyres to reduce friction. Add a wind turbine to recover all that wasted air resistance, and you're set. |
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<Heathen King, with longsword and shield> |
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Is this a metal sword. If so you'll stick to the bottom of the car too... |
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If not, you can weld it on with some duct tape. That sword should help the car slice through the air. |
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As it happens, my sword is a very faithful reproduction of a
classic Viking weapon in all respects save that it has a
stainless steel blade--nearly non-ferrous. Now while I still
have it drawn, let's discuss the differences between
adhesion and welding... |
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Steel that contains no iron content... hmmm... not so sure about that classification system. |
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Do I have to explain how stainless steel works? |
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Fukkit, I will anyway. Yes, it
contains Iron; quite a lot of it. It also contains a bit of
Carbon, which is what makes it steel. Unlike ferrous forms
of steel, however, it any given type of stainless also
incorporates secondary alloying agents in different
combinations and ratios, including but not limited to
Nickel, Chromium, Manganese, and in rare cases,
Berrylium. These seasonings alter the recipe enough to
change the crystal structure, making it 'non-magnetic',
although the degree to which this is true is subjective. It is
made 'stainless' by a thin 'film' of oxidized
material layering the crystalline matrix, usually Chromium
Oxide, preventing the Iron itself from oxidizing. The matrix
is susceptible to free Carbon bonding, which corrupts some
alloys and can cause a bit of rust, so don't hone your fancy
kitchen knives with a carbide sharpener. |
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Ah, I see: 'non-ferrous' vs. 'non-magnetic'. I'll explain that
as well. I work in an industry characterized by its noted
lack of scientists, at least formally-educated ones. Thus,
the two terms have become synonymous in the lexicon of
welders and fabricators. Bit of a slip there. Please
disregard my previous haughtiness, in this case. I'll leave it
there anyway, as it's a rather good description for those
interested in the topic but disinclined to read more than a
single paragraph. |
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Cars in the same country might also unexpectedly mount one another on following too close. This would produce excellent mileage for the one on top. |
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Not to mention making more cars <link>. |
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