Well, I got a 90%, (also got messed up on worm gears) but I think
there's room to quibble on two others.
#15 presumes a frictionless pulley - I live in the real world and know
that a straight lift with no pulley requires the least force.
#31 has no correct answer stated. The correct answer is 60 since the
actual mechanical ratio for the lever is 5:1.
I had the same problems with poorly written questions in college. My
professors did not seem amused...
firstname.lastname@example.org (Doug Miller) fired this volley in
I thought just a moment about that, then considered that the switch and
power are ALWAYS in series when supplying a load.... <G> the nature of a
circuit is expressed concerning the load arrangement, not the power
One question I found ambiguous, because two answers are true to some
degree was the one about the normally aspirated engine. Yes, atmospheric
pressure pushes the air charge in, but it wouldn't push it in unless
"suction" (lowered pressure) were created by the piston moving down.
I agree, Lloyd. I also had a question about the pressure differential
in the venturi setup. I think tube A would have some height in it while
tube B would be evacuated. I also question the direction of rotation on
the worm gear.
Perhaps not by diesel mechanics. They're treated the same as any
other circuit element in circuit network analysis. For example, they
are sometimes used in parallel with other circuit elements, as in the
question with three light bulbs.
Still not considered a part of the load though, Don. As an amateur radio
operator (N5COT) and an Air force electronics tech. we never considered
a switch as p[art of the load. It is part of the pathway to the load
But switches can make logic arrays. In particular with relay
logic. An example on a CNC machine could be a series of switches (axis
limit switches) in series, with a parallel set of contacts on a manual
override switch (which would also limit axis speeds to a minimum to
allow you to move the axis with problems away from the limit switch.
And for normal automotive applications, there are multiple door
switches in parallel to control the dome light -- and those are in
series with a master switch which often has three positions:
1) Dome light *always* off.
2) Dome light switched by door switches. Any single door, or any
combination of doors open turns on the light, otherwise it is
3) Dome light *always* on.
So -- they can reasonably be referred to as being in
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But nowadays the dome light is probably controlled by the output of some
damn computer and you'd have to be a digital Houdini to figure it all out.
The dome lights in our two "21st century" cars slooooooowly dim down to
off under certain conditions of the doors, ignition, ambient lighting
and G-d only knows what else. I haven't bothered to study that enough to
understand it. That slow dimming to off suggest to me what dying might
feel like someday. <G>
I think they got that one wrong as well. They seem to be assuming the
center of mass of the two boxes is out at their far edges (that gives
their answer, anyway).
I'd also quibble with 44 -- you have to know a bit more about what's
going on downstream before you can predict what's going to happen in
tube B. If the tube ends at the edge of the picture, you could get a
vacuum in tube B...
There are some more where I got their answer, but I think other answers
are equally valid: I got their answer for 48, but "suction" is just as
good an answer for a mechanical aptitude test (it would be wrong in a
physics test). Likewise for 49, what do they mean by "easiest"?
Again, I got their answer, but I note diesel can be ignited with no
spark at all.
Course not -- we know what the questions mean, you should read our
minds! (I am a professor, and I'm joking)
Note -- I got 92. Missed the worm drive, two of the pulley questions
had similar enough pictures that I thought I'd mis-clicked and missed
one as a result, and the two quibbles above.
On Thu, 18 Oct 2007 21:41:54 -0700, with neither quill nor qualm, "Jon
I got the gears but missed some of the pulleys, then I misread the
balloon/atmosphere question. 84% here.
P.S: Did you find any of that polyester lead yet? <titter>
History is often stranger than fiction. Fiction has to be plausible.
History is what happens when people don't follow the script.
--pete flip, RCM
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