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Lost
on the highway of science
Just
cause it's in black and white, is it true? Not according to a recent survey
of 12 popular middle-school science texts, which found repeated errors.
Using rather faint praise ("nonsense," "typically inaccurate," "typical
incorrect picture," and "gives credence to the new age nonsense") the report
homed in on major errors and misleading statements alike.
Here are some of
our faves:
Mistaking
the gas pedal for the engine: "An acceleration is a change in velocity
that results from speeding up, slowing down, or changing direction."
Hodgepodge! Acceleration is the change in velocity per unit of time,
not just a change in velocity. And by definition, a change in
velocity is a speeding up, slowing down, or changing direction.
It does not "result from speeding up, slowing down, or changing
direction."
The
1956 Studebaker Hawk is an amazing car, but it won't accelerate
unless a force is exerted on it. You wouldn't know that from some
science texts...
Bill
Jackameit's Studebaker
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Breaking the law,
physics-wise: Newton's first law of motion does not, as one textbook
claimed, say "an object in motion will remain in motion unless acted
upon by an outside force," unless you add at a constant velocity.
In other words, a
1956 Studebaker Hawk won't turn a corner without someone yanking on the
steering wheel. If it did, it would get busted by Cap'n Newton of the
physics police!
Printing
scam diagrams showing particles in solids, liquids and gases and implying
that the density of a liquid is close to that of gas. Actually, liquids
are closer to solids, which is why a liter of liquid gasoline packs
more energy than a liter of hydrogen
gas.
Making
gray while the sun shines: Implying that the sun
emits only infra-red energy. Open the driver's-side window, folks, and
notice that the highway is bathed in sunlight -- in the visible spectrum
(you can't see infra-red).
The report,
by John Hubisz, visiting professor of physics, of North Carolina State
University, is only part of the ongoing battle between textbook publishers
and scientists (see "Science Texts..." and "Errant Texts" in the bibliography
or this material on textbook
analysis).
When you're
ignorant, you know it, right?
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