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The Natural Philosopher[_2_] The Natural Philosopher[_2_] is offline
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Default More on electric cars.

Dave Plowman (News) wrote:
In article ,
The Natural Philosopher wrote:
Or an aircraft designer. Enough to create a pressure difference big
enough to keep a plane up.
Planes have wings specifically designed to produce lift. Only the most
stupid card designer would use the same effect.

I am beginning to wonder about you Dave.


You aren't Drivel under a new name are you?


Just answering your irrelevances with some of my own...

All of formula 1 is about aerodynamics - using air pressure to produce
lift downwards..


Which makes for inefficiency. It may well help the car to corner faster -
but in doing so will use more energy. You don't get out for nowt.


Oh. You have moved the goalposts AGAIN. You contention was that cars
dint cause air pressure changes.

Air pressure changes are inevitable in any body moving through air. When
these result in turbulence and vortices these become where the energy
goes that causes the actual profile drag.


Skin friction is also an affect, but at car sizes and speeds is not a
huge component.


What dominates low speed drag is a more or less constant rolling
resistance due to tyre deformation: What dominates higher speeds is air
resistance associated with pressure changes and vortex formation round
the bodywork


If it were only tyre rolling resistance, how do you explain 4WD being
markedly heavier on fuel than 2WD?

Largely because they are built like tanks



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Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to
lead are elected by the least capable of producing, and where the
members of society least likely to sustain themselves or succeed, are
rewarded with goods and services paid for by the confiscated wealth of a
diminishing number of producers.