Metalworking (rec.crafts.metalworking) Discuss various aspects of working with metal, such as machining, welding, metal joining, screwing, casting, hardening/tempering, blacksmithing/forging, spinning and hammer work, sheet metal work.

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Default Mechanical Aptitude Test

Found this site on RMH, posted here for
your enjoyment:

http://tinyurl.com/379fuh

Look for the review button to see your
test results.
Phil Kangas



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"Phil Kangas" wrote:
Found this site on RMH, posted here for
your enjoyment:

http://tinyurl.com/379fuh

Look for the review button to see your
test results.


Interesting, thanks. I got an 82%, most of which were gear issues, half of
which were due to over-confidence on simple ones (my achilles heal).

Jon


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kinda amusing - I got 92% - at least once I hit the wrong answer and hit
submit just as my brain said "that's wrong" -

I wonder if the test results correlate with anything

"Jon Danniken" wrote in message
...
"Phil Kangas" wrote:
Found this site on RMH, posted here for
your enjoyment:

http://tinyurl.com/379fuh

Look for the review button to see your
test results.


Interesting, thanks. I got an 82%, most of which were gear issues, half
of which were due to over-confidence on simple ones (my achilles heal).

Jon




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Jon Danniken wrote:

"Phil Kangas" wrote:
Found this site on RMH, posted here for
your enjoyment:

http://tinyurl.com/379fuh

Look for the review button to see your
test results.


Interesting, thanks. I got an 82%, most of which were gear issues, half of
which were due to over-confidence on simple ones (my achilles heal).

Jon


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...

Carla
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On Thu, 18 Oct 2007 21:41:54 -0700, with neither quill nor qualm, "Jon
Danniken" quickly quoth:

"Phil Kangas" wrote:
Found this site on RMH, posted here for
your enjoyment:

http://tinyurl.com/379fuh

Look for the review button to see your
test results.


Interesting, thanks. I got an 82%, most of which were gear issues, half of
which were due to over-confidence on simple ones (my achilles heal).


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

--
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History is what happens when people don't follow the script.
--pete flip, RCM


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In article ,
Larry Jaques wrote:


Interesting, thanks. I got an 82%, most of which were gear issues, half of
which were due to over-confidence on simple ones (my achilles heal).


I got 92%, fiddling around. It was not a bad test overall. It did have
some ambiguous questions.


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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In article , Carla Fong wrote:

94% here (also messed up the worm gears)

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...


And also #24, which they describe as a parallel circuit. Sure, the two lamps
are in parallel -- but they're in series with the switch...

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It's time to throw all their damned tea in the harbor again.
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Hmmmmm.......... 94%
1 error due to clicking the wrong button, the other two have some poorly
worded questions: are the fans direction specified as both from the
front/rear of each or viewed as a system? And gear drive nomenclature
could use a bit of work.

Phil Kangas wrote:
Found this site on RMH, posted here for
your enjoyment:

http://tinyurl.com/379fuh

Look for the review button to see your
test results.
Phil Kangas



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On Tue, 16 Oct 2007 09:07:11 -0400, "Phil Kangas"
wrote:

Found this site on RMH, posted here for
your enjoyment:

http://tinyurl.com/379fuh

Look for the review button to see your
test results.
Phil Kangas



94% kind of fun.....


Thank You,
Randy

Remove 333 from email address to reply.


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Carla Fong writes:

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 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.

I had the same problems with poorly written questions in college. My
professors did not seem amused...


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.
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Phil Kangas wrote:
Found this site on RMH, posted here for
your enjoyment:

http://tinyurl.com/379fuh

Look for the review button to see your
test results.
Phil Kangas




That was fun!

Got any more?
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Doug Miller wrote:

In article , Carla Fong wrote:

94% here (also messed up the worm gears)


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...



And also #24, which they describe as a parallel circuit. Sure, the two lamps
are in parallel -- but they're in series with the switch...


Switches are not considered as part of the circuit for series/parallel
determination.

Jim Chandler
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Lloyd E. Sponenburgh wrote:

(Doug Miller) fired this volley in
t:


In article , Carla Fong
wrote:

94% here (also messed up the worm gears)


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...


And also #24, which they describe as a parallel circuit. Sure, the two
lamps are in parallel -- but they're in series with the switch...



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
source.


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.

LLoyd


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.

Jim Chandler


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"SteveB" wrote in message
...
I got just under a failing grade, and found the test to be crappy. As
already pointed out, some of the questions were ambiguous, and there
weren't a lot that applied to real world situations, but more to theory.

Steve


The people who write tests dont deal in real world situations, its all
academic to them. They get paid the same weather thier right or wrong.

Best Regards
Tom.



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"Phil Kangas" wrote in message
.. .
Found this site on RMH, posted here for
your enjoyment:

http://tinyurl.com/379fuh

Look for the review button to see your
test results.
Phil Kangas


I got just under a failing grade, and found the test to be crappy. As
already pointed out, some of the questions were ambiguous, and there weren't
a lot that applied to real world situations, but more to theory.

Steve


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azotic wrote:

"SteveB" wrote in message
...

I got just under a failing grade, and found the test to be crappy. As
already pointed out, some of the questions were ambiguous, and there
weren't a lot that applied to real world situations, but more to theory.

Steve



The people who write tests dont deal in real world situations, its all
academic to them. They get paid the same weather thier right or wrong.

Best Regards
Tom.




And your score, Tom?
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I missed the hydraulic pressure one with the venturi and two columns. Also
#18, but i disagree with the result, as there seems to be no mechanical
advantage or reduction in the diagram.


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Phil Kangas wrote:

Found this site on RMH, posted here for
your enjoyment:

http://tinyurl.com/379fuh

Look for the review button to see your
test results.
Phil Kangas




92% but I had the same sorts of concerns about the ambiguous ones as
others have already posted.

If a switch can't be considered a series element in a circuit why do we
tend to say, "Just put a switch in series with it." ???

Because of question 31, I don't think even Einstein could have scored
100% unless he just tossed a dart at the answers to that question and
"got lucky".

Jeff

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In article 2D4Si.16$od4.13@trnddc04, Jim Chandler wrote:

I also question the direction of rotation on the worm gear.


I did too; I thought they'd made a mistake. After the third look at it,
though, I decided the answer given is correct.


--
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Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.
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Jeff Wisnia wrote:
Phil Kangas wrote:

Found this site on RMH, posted here for
your enjoyment:

http://tinyurl.com/379fuh

Look for the review button to see your
test results.
Phil Kangas




92% but I had the same sorts of concerns about the ambiguous ones as
others have already posted.

If a switch can't be considered a series element in a circuit why do we
tend to say, "Just put a switch in series with it." ???

Because of question 31, I don't think even Einstein could have scored
100% unless he just tossed a dart at the answers to that question and
"got lucky".

Jeff


A switch is ALWAYS in series with the ENTIRE CIRCUIT, just not
considered as a component of the load.

Jim Chandler
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On Tue, 16 Oct 2007 09:07:11 -0400, "Phil Kangas" wrote:

Found this site on RMH, posted here for
your enjoyment:

http://tinyurl.com/379fuh

Look for the review button to see your
test results.
Phil Kangas


100%. But the boxes on the see-saw question didn't have the correct choice
available, so I chose the only one that seemed to fit...


Mark Rand
RTFM
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"Mark Rand" wrote in message
news
On Tue, 16 Oct 2007 09:07:11 -0400, "Phil Kangas"
wrote:

Found this site on RMH, posted here for
your enjoyment:

http://tinyurl.com/379fuh

Look for the review button to see your
test results.
Phil Kangas


100%. But the boxes on the see-saw question didn't have the correct choice
available, so I chose the only one that seemed to fit...


Right you are. Somebody didn't realize where the center of effort was.

--
Ed Huntress


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On Fri, 19 Oct 2007 20:55:48 +0100, Mark Rand
wrote:

On Tue, 16 Oct 2007 09:07:11 -0400, "Phil Kangas" wrote:

Found this site on RMH, posted here for
your enjoyment:

http://tinyurl.com/379fuh

Look for the review button to see your
test results.
Phil Kangas


100%. But the boxes on the see-saw question didn't have the correct choice
available, so I chose the only one that seemed to fit...


100% for me, too. Re the poorly formulated questions, sometimes you
need to put aside your annoyance with the limits of the information
presented and make a decision. Context can help, and the test would
have been easier if it were possible to navigate back and forth - in
some cases the correct answer was apparent only after seeing the next
question.

--
Ned Simmons


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Ed Huntress wrote:
"Mark Rand" wrote in message
news
On Tue, 16 Oct 2007 09:07:11 -0400, "Phil Kangas"
wrote:


Found this site on RMH, posted here for
your enjoyment:

http://tinyurl.com/379fuh

Look for the review button to see your
test results.
Phil Kangas


100%. But the boxes on the see-saw question didn't have the correct choice
available, so I chose the only one that seemed to fit...



Right you are. Somebody didn't realize where the center of effort was.

--
Ed Huntress




Yeabut - it was the only one in the ball park...

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I managed 96% but found a few a bit ambiguous. Here's to another one
with clearer questions.


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In article ,
cavelamb himself wrote:

Phil Kangas wrote:
Found this site on RMH, posted here for
your enjoyment:

http://tinyurl.com/379fuh


This leads me to
http://www.forddoctorsdts.com/quizzes/MechanicalAptitude.php which
mentions no tests, and takes me to http://www.turbotraining.com/.

How do I find this test? All I see are offers of training courses.

Joe Gwinn
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On Fri, 19 Oct 2007 16:30:53 -0400, Ned Simmons wrote:
On Fri, 19 Oct 2007 20:55:48 +0100, Mark Rand
wrote:

On Tue, 16 Oct 2007 09:07:11 -0400, "Phil Kangas" wrote:

Found this site on RMH, posted here for
your enjoyment:

http://tinyurl.com/379fuh


90%. Missed #7 (overdrive vs. reduction), #9 (worm drive; my eyes got
all buggy or something?), #19 (5 pulley lift force), #31 (How does that
box weigh 50Kg exactly please? What am I missing?), and #48 (why does
air enter the engine cylinder - suction or atmoshpheric pressure? How
are those different exactly in this context?)

Not bad for someone who works on computers for a living, I guess.

Dave


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Joseph Gwinn wrote:
In article ,
cavelamb himself wrote:


Phil Kangas wrote:

Found this site on RMH, posted here for
your enjoyment:

http://tinyurl.com/379fuh



This leads me to
http://www.forddoctorsdts.com/quizzes/MechanicalAptitude.php which
mentions no tests, and takes me to http://www.turbotraining.com/.

How do I find this test? All I see are offers of training courses.

Joe Gwinn


http://www.forddoctorsdts.com/quizze...alAptitude.php


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gunsmith wrote:

I managed 96% but found a few a bit ambiguous. Here's to another one
with clearer questions.



Yepper! That one's a toughie, all right.
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On Fri, 19 Oct 2007 16:55:04 -0500, Robert Swinney wrote:
Did you ever hear the one "Nature abhors a vacuum." Pull the air out of anything and gravity
pushing on the atmosphere causes it (the air) to rush in. Suction really has nothing to do with it,
except that was the method used to eliminate the air. Gasses can be eliminated in other ways, such
as the "getter" in the envelope of a vacuum tube at evacuation.


Oh, agreed, but both answers are equally wrong. The reason the "air"
goes in there is because there's a pressure differential. Which in
every car I've owned for the last decade or more has been
turbine-compressed. So suction is at least as accurate as "atmospheric
pressure". Ah well, not like I'm being graded on it, and a 90% vs a 92%
is the same letter grade regardless of the scale, I think.

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Joseph Gwinn writes:

In article ,
cavelamb himself wrote:

Phil Kangas wrote:
Found this site on RMH, posted here for
your enjoyment:

http://tinyurl.com/379fuh


This leads me to
http://www.forddoctorsdts.com/quizzes/MechanicalAptitude.php which
mentions no tests, and takes me to http://www.turbotraining.com/.


I just typed the link you posted, and got the page introducing the
test.
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According to Jim Chandler :
Doug Miller wrote:


[ ... ]

And also #24, which they describe as a parallel circuit. Sure, the two lamps
are in parallel -- but they're in series with the switch...


Switches are not considered as part of the circuit for series/parallel
determination.


Unless there is a series/parallel arrangement of switches to
implement "and" and "or" conditions.

Enjoy,
DoN.

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"cavelamb himself" wrote in message
...
azotic wrote:

"SteveB" wrote in message
...

I got just under a failing grade, and found the test to be crappy. As
already pointed out, some of the questions were ambiguous, and there
weren't a lot that applied to real world situations, but more to theory.

Steve



The people who write tests dont deal in real world situations, its all
academic to them. They get paid the same weather thier right or wrong.

Best Regards
Tom.


And your score, Tom?


98

Best Regards
Tom.





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On Fri, 19 Oct 2007 18:42:22 -0500, Robert Swinney wrote:
Agreed ? Turbo-charging does nothing more than artificially increase atmospheric pressure -


Er, well, atmospheric pressure is 1 bar. My turbo puts out 1.6someting
bar. So, what forces air into _my_ engine's chambers is only somewhat
atmospheric pressure.

or
raise thin atmosphere to more nearly "ground pressure", such as in the case of high flying
piston-type aircraft. IMO, suction is not a very accurate description of why fuel is drawn into a
combustion chamber.


Yup, that answer equally sucks. When I was a college student I would
have been pretty damn intense about this ****ty question and the fact
that both wrong answers suck equally but I'm having a hard time caring


All non-Diesel piston engines are considered to be normally aspirated, AFAIK.
(someone will correct me, I'm sure) Suction is merely a way of ingesting more stoichoimetric air
and fuel mixture. The earliest IC engines had no compression, thus no suction was present.


And yet, in the last century, so little has changed in toe otto cycle
engine. Isn't that remarkable?

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I got 98%. The only one I got wrong was the governor, because I assumed
the ring was fixed and the shaft could move.

A lot of the questions were ambiguous though, and could have multiple
interpretations. I got lucky there, because the alternate (or more
correct) answer wasn't one of the options.

One of the lever questions was just plain wrong, IMHO.

--
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http://thespamdiaries.blogspot.com/
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On Fri, 19 Oct 2007 16:05:14 GMT, Jim Chandler wrote:

Doug Miller wrote:

In article , Carla Fong wrote:

94% here (also messed up the worm gears)


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...



And also #24, which they describe as a parallel circuit. Sure, the two lamps
are in parallel -- but they're in series with the switch...


Switches are not considered as part of the circuit for series/parallel
determination.

Jim Chandler


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.

98.

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On Fri, 19 Oct 2007 16:55:04 -0500, "Robert Swinney"
wrote:

Did you ever hear the one "Nature abhors a vacuum." Pull the air out of anything and gravity
pushing on the atmosphere causes it (the air) to rush in. Suction really has nothing to do with it,
except that was the method used to eliminate the air. Gasses can be eliminated in other ways, such
as the "getter" in the envelope of a vacuum tube at evacuation.


A correct answer would be "due to pressure differential". Manifold
pressure is seldom atmospheric. It's often lower (engine vacuum) in
an ordinary engine but it might be higher in a turbocharged engine.
"Suction" is created by a lower pressure region causing a pressure
differential, so "suction" is closer to right in this case.
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"Don Foreman" wrote in message
...
On Fri, 19 Oct 2007 16:55:04 -0500, "Robert Swinney"
wrote:

Did you ever hear the one "Nature abhors a vacuum." Pull the air out
of anything and gravity
pushing on the atmosphere causes it (the air) to rush in. Suction really
has nothing to do with it,
except that was the method used to eliminate the air. Gasses can be
eliminated in other ways, such
as the "getter" in the envelope of a vacuum tube at evacuation.


A correct answer would be "due to pressure differential". Manifold
pressure is seldom atmospheric. It's often lower (engine vacuum) in
an ordinary engine but it might be higher in a turbocharged engine.
"Suction" is created by a lower pressure region causing a pressure
differential, so "suction" is closer to right in this case.


The trouble with that is that "suction," like "centrifugal force," is not a
term that scientists or most engineers would accept, except in casual
conversation. Suction is just the result of a lower pressure acting
differentially to a higher pressure; centrifugal force is just the effect of
acceleration against the true force involved, which is the centripetal
force.

When I see "suction" used in a technical discussion I can accept it as a
casual term and assume that the person speaking, if he or she is technically
knowledgeable, knows there really is no such thing as "suction," as a real
force. But I'm not used to seeing it on a test of technical subjects.

There really is no "suction." And there really is no "centrifugal force."
They're useful concepts but they aren't technically correct.

--
Ed Huntress


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