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Test your mechanical aptitude
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tony barnhill
Great Pumpkin - R.I.P
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<div class="ubbcode-block"><div class="ubbcode-header">Quote:]I'd think either suction or atmospheric pressure would be the correct answer(s).[/QUOTE]
WHEW! I chose 'suction' & couldn't figure out why I was wrong.
WHEW! I chose 'suction' & couldn't figure out why I was wrong.
WHEW! I chose 'suction' & couldn't figure out why I was wrong.tony barnhill said:
[/QUOTE]
I also choose suction. I think the difference is that we are "gasoline" types and are used to thinking in terms of vacuum levels in the manifold. The quiz was put together by "diesel" people they don't have vacuum in their manifolds, they have full atmospheric pressure.
Twosheds
Darth Vader
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88%. I had Brain Fade on a couple.
I say that it is the pressure differential between the higher atmospheric pressure and the lower pressure in the cylinder that forces the fuel/air mixture into the cylinder.
This is because I am an aircraft mechanic and we measure the Absolute Pressure in the manifold. Absolute pressure means that we think of zero pressure as no pressure at all, like outer space. So the manifold pressure is a lower positive number than atmospheric pressure. We don't say "suction".
Car mechanics measure the manifold pressure in gauge pressure, which considers atmospheric pressure to be zero, so, on a normally-aspirated engine, the pressure would be a negative number, which they call "suction".
So either answer would be correct, since it's the difference in pressure that matters.
Also, kilograms are not a unit of force or weight, but mass. Not that it makes a difference.
I say that it is the pressure differential between the higher atmospheric pressure and the lower pressure in the cylinder that forces the fuel/air mixture into the cylinder.
This is because I am an aircraft mechanic and we measure the Absolute Pressure in the manifold. Absolute pressure means that we think of zero pressure as no pressure at all, like outer space. So the manifold pressure is a lower positive number than atmospheric pressure. We don't say "suction".
Car mechanics measure the manifold pressure in gauge pressure, which considers atmospheric pressure to be zero, so, on a normally-aspirated engine, the pressure would be a negative number, which they call "suction".
So either answer would be correct, since it's the difference in pressure that matters.
Also, kilograms are not a unit of force or weight, but mass. Not that it makes a difference.
G
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piman said:
I last studied in college in 1966. The bad news is I was graduated in 1970!
For all you you out there that passed that test, kiss my independent rear suspension.
healeylvr57
Senior Member
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80% and I also disagree with the answer on piston suction
Jeff_Sigrist
Member
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98%, but I took my time.
Jeff
Jeff
judow
Darth Vader - R.I.P
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/bcforum/images/%%GRAEMLIN_URL%%/cheers.gif Okay - I admit it! I failed, got 50. However...that was better than I thought I would get. Yes, I'm female and haven't been emerged in the mechanics of the combustion engine. I am, however, learning and I am logical. So much for making excuses....
bugimike
Yoda
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TR6BILL said:piman said:
I last studied in college in 1966. The bad news is I was graduated in 1970!
For all you you out there that passed that test, kiss my independent rear suspension.
/bcforum/images/%%GRAEMLIN_URL%%/lol.gif /bcforum/images/%%GRAEMLIN_URL%%/lol.gif Class of '69 meself!! /bcforum/images/%%GRAEMLIN_URL%%/banana.gif /bcforum/images/%%GRAEMLIN_URL%%/banana.gif /bcforum/images/%%GRAEMLIN_URL%%/devilgrin.gif
T
TRDejaVu
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82%.
Bonus question:
If the angle of the dangle is congruent to the reciprocal of the tangent, what time is it in Newfoundland on a Tuesday?
Bonus question:
If the angle of the dangle is congruent to the reciprocal of the tangent, what time is it in Newfoundland on a Tuesday?
tony barnhill
Great Pumpkin - R.I.P
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3:30pm if magnetic declination is <3-degrees.
T
TRDejaVu
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Good effort, but I said Tuesday not Sunday.
tony barnhill
Great Pumpkin - R.I.P
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Ah, can't call that mistake dislexia, can I? Do you want me to calculate Greenwich Mean time, Zulu time, or local?