Simple Machines B/Compound Machines C

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Re: Simple Machines B/Compound Machines C

Postby Unome » April 27th, 2015, 3:38 pm

[math]8.7 kg * 1864 m * 9.8067 m/s^2 = 160 kJ[/math] with significant figures
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Re: Simple Machines B/Compound Machines C

Postby UTF-8 U+6211 U+662F » April 27th, 2015, 3:41 pm

[math]8.7 kg * 1864 m * 9.8067 m/s^2 = 160 kJ[/math] with significant figures
160000 J

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Re: Simple Machines B/Compound Machines C

Postby Unome » April 27th, 2015, 4:33 pm

Since there haven't been many wheel & axle problems:

What is the distance traveled by the green point for every rotation of the 12 spur gear? (Round to hundreths)
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Re: Simple Machines B/Compound Machines C

Postby plaid suit guy2 » April 27th, 2015, 4:46 pm

Since there haven't been many wheel & axle problems:

What is the distance traveled by the green point for every rotation of the 12 spur gear? (Round to hundreths)
Is the drawing weird, or is this an eccentric shaft? Assuming it's not an eccentric (though I don't think it will make a difference).
Okay so
12/20*4π=7.54
The wheel and axle don't matter. One rotation on the input of the axle is one rotation on the output of the axle
EDIT: actually, yeah, an eccentric would make this some kind of cycloid, which is longer than a circle...
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Re: Simple Machines B/Compound Machines C

Postby Unome » April 27th, 2015, 5:12 pm

No, it's not eccentric, sorry And I don't think that's correct.
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Re: Simple Machines B/Compound Machines C

Postby plaid suit guy2 » April 27th, 2015, 5:20 pm

Can you explain your reasoning? The way I see it, the small gear makes the big gear rotate 60% of a rotation, which is directly connected to the wheel, and therefore must also go through 60% of a rotation. Thus it's just 60% of it's circumference of 4πm, which is 7.34m
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Nationals 2012:
Sound of Music: 8th

Nationals 2013:
Remote Sensing: 1st
ELG: 1st
MagLev: 6th

State 2014:
Boomi: 1st (scored 1824)
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Compound: 3rd
Malgev: 1st
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total gold: 18
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total bronze: 5
6th: 1
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Re: Simple Machines B/Compound Machines C

Postby Unome » April 27th, 2015, 5:31 pm

Can you explain your reasoning? The way I see it, the small gear makes the big gear rotate 60% of a rotation, which is directly connected to the wheel, and therefore must also go through 60% of a rotation. Thus it's just 60% of it's circumference of 4πm, which is 7.34m
My reasoning was that the size of the circle made by the green point is equal to the size of the circle made by the center of the axle; since the axle is 0.65 meters offset from the center of the 20 spur gear, the circumference of that would be 1.3π, multiplied by 60% is 2.45... I think I just answered my own question. Anyway, I'll just give you the next turn.
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Re: Simple Machines B/Compound Machines C

Postby plaid suit guy2 » April 27th, 2015, 5:35 pm

Yeah, that is an eccentric path. Which was the other path, but that dot would probably describe some awful combination of the two rotations that I doubt either of us could imagine or derive in our head if it is the eccentric.

How hard do you want the question to be?
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Nationals 2012:
Sound of Music: 8th

Nationals 2013:
Remote Sensing: 1st
ELG: 1st
MagLev: 6th

State 2014:
Boomi: 1st (scored 1824)
Circuits: 1st
Compound: 3rd
Malgev: 1st
MP: 2nd

total gold: 18
total silver: 10
total bronze: 5
6th: 1
Poudre High School class of '15

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Re: Simple Machines B/Compound Machines C

Postby Unome » April 27th, 2015, 5:43 pm

Yeah, that is an eccentric path. Which was the other path, but that dot would probably describe some awful combination of the two rotations that I doubt either of us could imagine or derive in our head if it is the eccentric.

How hard do you want the question to be?
If the non-spur wheel isn't off-center, then how is it eccentric? The green dot should have the same trajectory as the axle.
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Re: Simple Machines B/Compound Machines C

Postby plaid suit guy2 » April 27th, 2015, 5:50 pm

What you're saying sounds like it does this.
blue and yellow plaid suit
Nationals 2012:
Sound of Music: 8th

Nationals 2013:
Remote Sensing: 1st
ELG: 1st
MagLev: 6th

State 2014:
Boomi: 1st (scored 1824)
Circuits: 1st
Compound: 3rd
Malgev: 1st
MP: 2nd

total gold: 18
total silver: 10
total bronze: 5
6th: 1
Poudre High School class of '15


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