Mohaughn: I haven't taken physics in quite some time, but isn't it 32 ft/s/s? (I may be wrong, but 32 sounds more familiar than 22)
AJ
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Mohaughn: I haven't taken physics in quite some time, but isn't it 32 ft/s/s? (I may be wrong, but 32 sounds more familiar than 22)
AJ
Quote:
Originally posted here by avdven
Mohaughn: I haven't taken physics in quite some time, but isn't it 32 ft/s/s? (I may be wrong, but 32 sounds more familiar than 22)
AJ
Thanks for the correction.. It is 32.. Not sure if that was a typo or a brainfart..
mohaughn, i had to study your logic to understand it, when i did, it all came so clear, that was brilliant!
Thanks zepherin for an intriguing post. do it again! yeah! do it again!
mohaughn, correct me if i'm wrong, but thats in freefall, not on an in-cline. Its the friction your talking about that will make it work. The different cannonball will have different inirtia. This difference in inirtia will cause it to roll against the friction faster or slower. 32/ft/s^2, absolutly not on an incline. I could make the incline 1 degree below horizontal and it would take about ten minutes for it to get up to that speed. 32ft/s^2 only in freefall
Neg's post is dead on.
The quickest way to come to that conclusion (but lacking the incredibly thorough detail Neg included in his post) is by the simple idea that for each unknown, you are dividing the pile once.
In this scenario, there are two unknowns: whether the ball is lighter/heavier, and which ball it is.
So we need to perform 2 equal divisions, and end up with three identical piles. Negative's method is dead on. :)
I was just curious. Didn't I make a post about copying and pasting earlier today, and how quoting sources is illegal. Gee, maybe Negative is right and I do have to write a tutorial on it. It is really bad when you don't even cite your source.....
We (my logic class group) solved it in a similar way to negative, http://www.antionline.com/showthread...=541833#541833 my math teacher (different class) used a wicked line of semitry rule and stacked them like bowling pins (10 of them) and kept restacking them, and then wrote a formula on how many minimum times it would take for any n amount of cannon balls.
Well, since he never did post a source......
http://www.greenspun.com/bboard/q-an...?msg_id=003Tgo
does that look kinda familiar to anyone....
about 3/4 of the way down the page.....Quote:
It appears I am going to have to defend the army here and show where
the country gets its smarts from...no offence navy...
Take the 12 balls and devide them into 3 groups of four and number
them from 1-12....now try and keep up navy boy...
1)Compare 1,2,3,4 to 5,6,7,8 if equal then the ball is in the third
group of 9,10,11,12. 2)Compare 1,2,3 with 9,10,11 if equal, the
answer is 12 and compare it to 1 to find out if it is heavier or
lighter. 3)If step 2 is not equal then compare 9 and 10, if equal
answer is 11. If step 3 is not equal choose the one that matches the
fulcrum tilt in step 2.
Now it gets tricky...4)If step 1 is not equal compare balls 1,2,3,5
to 4,10,11,12. You know from step one which way the tilt was and we
will assume it tilted down on the left..it doesn't matter. 5)If step
4 is equal then compare 6 to 7, if equal answer is 8 and it is the
light one. If not equal take the lighter one of 6&7. 6)If step 4
was not equal and tilted down on left side, compare 1 to 2, if equal the answer is 3 and it is heavy. If not equal choose the heavier of
1 & 2. 7) If step 4 tilted down on right side compare 4 to 9, if
equal then 5 is the the light ball, if not then 4 is the heavy ball.
The mass of an object is in no way a factor of it's inertia. The two factors that do come into play are the incline of the ramp and the inertia on the object caused by gravity. Galileo used ramps to prove that all objects fall at the same rate regardless of weight as long as the amount of friction is negligible.Quote:
Originally posted here by xmaddness
mohaughn, correct me if i'm wrong, but thats in freefall, not on an in-cline. Its the friction your talking about that will make it work. The different cannonball will have different inirtia. This difference in inirtia will cause it to roll against the friction faster or slower. 32/ft/s^2, absolutly not on an incline. I could make the incline 1 degree below horizontal and it would take about ten minutes for it to get up to that speed. 32ft/s^2 only in freefall
http://www.lightandmatter.com/htmlbook/bk1ch03.html
or search for Galileo's incline
Wow... the memories of taking physics. lol I never thought I could actually learn (or at least get refreshed) in Physics here. :-)
AJ