Tricky Puzzles - Topic 3

For discussion of non-Wonderland topics - please read rules!

Moderators: jdl, ~xpr'd~, tyteen4a03, Emerald141, Qloof234, Stinky

Post Reply
User avatar
Master Wonder Mage
Rainbow SuperStar
Posts: 2123
Joined: Sat Jan 08, 2011 5:26 pm

Post by Master Wonder Mage » Fri Mar 09, 2012 3:01 am

He juggles.
User avatar
LittleZbot
Rainbow MegaStar
Posts: 3036
Joined: Fri Jul 03, 2009 10:51 pm
Contact:

Post by LittleZbot » Fri Mar 09, 2012 3:22 am

Correct. With one video game always in the air, the bridge only had 149.8 pounds to support.
To Shorty, who was immortalized in an adventure.
To Marinus, who was my community older brother.
To Janet, who I will remember every time I wear a toque.

May these Wonderlanders find more adventures in passing than they ever had in life.
Muzozavr
Rainbow Spirit Chaser
Posts: 5562
Joined: Wed Jan 11, 2006 2:55 pm

Post by Muzozavr » Fri Mar 09, 2012 6:23 am

Actually, no, it doesn't. According to Newton's Third Law, every action has a counter-action, an equal force that's directed the opposite way. Basically, if your finger is pressing on a rock, the rock is pressing on your finger.

Therefore, the very act of juggling those videogames causes the juggler to exert a downward force on that bridge.

Had the force been equal to the weight of said games, it would maybe turn out to be possible by starting juggling before going across the bridge and keeping all 3 games in the air. So at any point he'd only have to counteract the weight of ONE game instead of three.

However, he also has to counteract the force of gravity to actually throw said games up. So that combined force is already enough to break the bridge. (And please don't make me calculate this -- it's a hard calculation whilst common sense tells me that even if it's somehow possible, then no real juggler would be able to do everything this perfectly)

In fact, juggling in this case is even worse than not juggling. :roll:

"Real" ways to do this:
1) Come back for one of those games later.
2) As long as the bridge is short enough, you could just throw the games across the bridge and then walk over it empty-handed. (:lol:)
3) The bridge doesn't respond directly to the weight. Like any other physical object, it responds to pressure. Said pressure is distributed evenly across the contact area. If you stand on your two legs, the contact area is too small, making for pressure that is too big for this particular point. So lie on your chest and start crawling towards the goal. Given how light those videogames are, it'll probably work.
4) But the safest way is to find another way to Guy's house and ignore the bridge entirely.
Rest in peace, Kym. I hardly knew ya.
Rest in peace, Marinus. A bright star, you were ahead of me on my own tracks of thought. I miss you.
Marinus
Rainbow AllStar
Posts: 4686
Joined: Sun Dec 16, 2007 2:20 pm

Post by Marinus » Fri Mar 09, 2012 5:39 pm

Interesting! 8)

I have to agree with Muzozavr: The total gravity forces of the three videogames are always (averagely during the way across the bridge) affecting the force of Guy's feet on the bridge. (There are no other forces to avoid them falling on the ground, then the forces on his body; no need to calculate. :wink: )

Also nice alternative solutions. Here are some more:

- He goes to the toilet first to reduce his weight.
- He goes running fast, quite a while for the same reason
- He also carries a big balloon with helium, to reduce his gravity force
- He uses his jacket or a fly-kite against the wind, for the same reason
Image
User avatar
Sammy_Bro
Rainbow Star
Posts: 1737
Joined: Thu May 07, 2009 8:58 pm

Post by Sammy_Bro » Fri Mar 09, 2012 6:42 pm

It doesn't matter as long Joe reaches Guy's house.
:D
MyNameIsKooky
Rainbow Spirit Master
Posts: 9495
Joined: Mon Dec 01, 2008 10:18 pm

Post by MyNameIsKooky » Fri Mar 09, 2012 7:34 pm

Muzozavr wrote:the very act of juggling those videogames causes the juggler to exert a downward force on that bridge.
I disagree. The only downwards force each video game would have on Guy and the bridge would be a normal force of 5.4 ounces. And that's only when Guy is making contact with the video game.
Muzozavr wrote:However, he also has to counteract the force of gravity to actually throw said games up. So that combined force is already enough to break the bridge.
Guy and the video games are not accelerating at all if Guy isn't juggling, therefore you can assume that for each object, the magnitude of their gravitational force would be equal to that of their normal force (5.4 ounces for each video game and 149 pounds for Guy). In order to accelerate a video game upwards to juggle, Guy would have to make his upwards normal force on the video game larger than 5.4 ounces in order to create a net force necessary to launch the video game into the air. When this happens, the downwards normal force on Guy from the video game remains unchanged, therefore throwing the games upwards in order to juggle does not affect anyone's normal force on the bridge.

Regardless, you have to wonder if it's even legal to build a bridge this fragile. :?
Marinus
Rainbow AllStar
Posts: 4686
Joined: Sun Dec 16, 2007 2:20 pm

Post by Marinus » Fri Mar 09, 2012 8:13 pm

MyNameIsKooky wrote:
Muzozavr wrote:the very act of juggling those videogames causes the juggler to exert a downward force on that bridge.
I disagree. The only downwards force each video game would have on Guy and the bridge would be a normal force of 5.4 ounces. And that's only when Guy is making contact with the video game.
Do you know what's the mass of an Uzi-bullet? I don't, but let's say about 100 to 200 gram, which means their gravity force on Earth is about 1 to 2 Newton .

So, if you lay on your back with such a bullet on your forehead, the force is about 1 to 2 Newton, right?

Now, imagine that I'm standing right in front of you with an Uzi in my hands, pointing at your forehead, what do you think how big the force will be, if I pull the trigger?


*shot* :lol:
Image
User avatar
Technos72
Rainbow MegaStar
Posts: 3227
Joined: Thu Nov 26, 2009 12:20 am

Post by Technos72 » Fri Mar 09, 2012 8:18 pm

Here's another hard puzzle

The answer is an answer
Image
Marinus
Rainbow AllStar
Posts: 4686
Joined: Sun Dec 16, 2007 2:20 pm

Post by Marinus » Fri Mar 09, 2012 8:27 pm

Technos72 wrote:Here's another hard puzzle

The answer is an answer
Then I quess the question is a question! 8)
Image
User avatar
Emerald141
Rainbow AllStar
Posts: 4551
Joined: Fri Dec 26, 2008 4:56 pm

Post by Emerald141 » Fri Mar 09, 2012 8:32 pm

An answer.

There, that was easy.
The Rest of the Story
My Level List

Seek light, brothers.
MyNameIsKooky
Rainbow Spirit Master
Posts: 9495
Joined: Mon Dec 01, 2008 10:18 pm

Post by MyNameIsKooky » Fri Mar 09, 2012 8:42 pm

Marinus wrote:
MyNameIsKooky wrote:
Muzozavr wrote:the very act of juggling those videogames causes the juggler to exert a downward force on that bridge.
I disagree. The only downwards force each video game would have on Guy and the bridge would be a normal force of 5.4 ounces. And that's only when Guy is making contact with the video game.
Do you know what's the mass of an Uzi-bullet? I don't, but let's say about 100 to 200 gram, which means their gravity force on Earth is about 1 to 2 Newton .

So, if you lay on your back with such a bullet on your forehead, the force is about 1 to 2 Newton, right?
0.1 to 0.2 Newtons, actually. *murdered*
Marinus wrote:Now, imagine that I'm standing right in front of you with an Uzi in my hands, pointing at your forehead, what do you think how big the force will be, if I pull the trigger?
The gun launches the bullet. After that, the only acceleration is due to gravity, so all of the x forces are balanced. Therefore, the bullet will only apply 0.1 to 0.2 N of force to my forehead.[/completely missing the point]

*shot for real*
Last edited by MyNameIsKooky on Fri Mar 09, 2012 9:48 pm, edited 1 time in total.
Marinus
Rainbow AllStar
Posts: 4686
Joined: Sun Dec 16, 2007 2:20 pm

Post by Marinus » Fri Mar 09, 2012 8:52 pm

Kooky, I must admit that you have a good sense of humor, but if you would like to survive for about 70 years from now on, I think you'd better make an appointment with your physics-teacher, for extra-education (don't know if that's a correct English word, and I'm too lazy to look it up) :lol:
Last edited by Marinus on Fri Mar 09, 2012 9:56 pm, edited 1 time in total.
Image
Marinus
Rainbow AllStar
Posts: 4686
Joined: Sun Dec 16, 2007 2:20 pm

Post by Marinus » Fri Mar 09, 2012 9:00 pm

OK, here is lesson 1:


Wikipedia says:

1 N is the force of Earth's gravity on a mass of about 100 g = (1⁄9.81 kg).
EDIT:

http://en.wikipedia.org/wiki/Newton_(unit)

I can't get the link working correct right now. I guess I've to add some % ascii code, instead of the underscore _ but I'm too lazy... :wink:
Image
Muzozavr
Rainbow Spirit Chaser
Posts: 5562
Joined: Wed Jan 11, 2006 2:55 pm

Post by Muzozavr » Fri Mar 09, 2012 9:35 pm

MyNameIsKooky wrote:
Muzozavr wrote:the very act of juggling those videogames causes the juggler to exert a downward force on that bridge.
I disagree. The only downwards force each video game would have on Guy and the bridge would be a normal force of 5.4 ounces. And that's only when Guy is making contact with the video game.
No. It's not the video game that puts the pressure on Joe. Try this: stay on the floor with something moderately heavy in your hands (experiment to find the best weight) and then try to raise both hands up very quickly. You'll have to exert upward force for that, right? During that you'll feel how your feet are "pressured" towards the ground for a short time. That's the downward force I'm talking about.

The very act of throwing that videogame up will cause his feet to exert an identical downward force on the bridge.
Rest in peace, Kym. I hardly knew ya.
Rest in peace, Marinus. A bright star, you were ahead of me on my own tracks of thought. I miss you.
User avatar
Technos72
Rainbow MegaStar
Posts: 3227
Joined: Thu Nov 26, 2009 12:20 am

Post by Technos72 » Fri Mar 09, 2012 9:37 pm

Emerald141 wrote:An answer.

There, that was easy.
Good. Maybe it's not hard after all :roll:
Image
MyNameIsKooky
Rainbow Spirit Master
Posts: 9495
Joined: Mon Dec 01, 2008 10:18 pm

Post by MyNameIsKooky » Fri Mar 09, 2012 9:47 pm

Marinus wrote:I think you'd better make an appointment with your physics-teacher, for extra-education
No, I just started taking physics this year, therefore I don't know what I'm talking about anyways.
Marinus wrote:OK, here is lesson 1:
I was taught that 9.81 N = 1 kg, not 100 g.
Marinus
Rainbow AllStar
Posts: 4686
Joined: Sun Dec 16, 2007 2:20 pm

Post by Marinus » Fri Mar 09, 2012 9:52 pm

MyNameIsKooky wrote:I was taught that 9.81 N = 1 kg, not 100 g.
That is correct. 1 kg = 1000 g

If 1000 g = 9.81 N (almost 10 N) then 100 g = almost 1 N
Image
MyNameIsKooky
Rainbow Spirit Master
Posts: 9495
Joined: Mon Dec 01, 2008 10:18 pm

Post by MyNameIsKooky » Fri Mar 09, 2012 9:54 pm

Oh. I'm an idiot. :oops:
Marinus
Rainbow AllStar
Posts: 4686
Joined: Sun Dec 16, 2007 2:20 pm

Post by Marinus » Fri Mar 09, 2012 10:20 pm

MyNameIsKooky wrote:Oh. I'm an idiot. :oops:
I wouldn't dare to say that. (But on the other hand I see no reason to disagree with you :wink: )

Anyhow, I hope you understand now that the speed of an object affects the forces of impact. If you jump out of an airplane without a parachute, the forces between your body and the Earth are pretty much bigger, then when you're just laying on the beach. :)
Image
User avatar
LittleZbot
Rainbow MegaStar
Posts: 3036
Joined: Fri Jul 03, 2009 10:51 pm
Contact:

Post by LittleZbot » Sat Mar 10, 2012 12:37 am

I didn't think about that. Sorry.
To Shorty, who was immortalized in an adventure.
To Marinus, who was my community older brother.
To Janet, who I will remember every time I wear a toque.

May these Wonderlanders find more adventures in passing than they ever had in life.
Marinus
Rainbow AllStar
Posts: 4686
Joined: Sun Dec 16, 2007 2:20 pm

Post by Marinus » Sat Mar 10, 2012 12:44 am

LittleZbot wrote:I didn't think about that. Sorry.
Don't worry. It was a nice puzzle anyways! :D
Image
User avatar
hoomdoom
Rainbow Keeper
Posts: 321
Joined: Fri Feb 24, 2012 11:23 pm

Post by hoomdoom » Sat Mar 10, 2012 1:48 am

What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?

ALSO

The following equation is wrong: 101 - 102 = 1

Move one numeral to make it correct.
Hoomdoom is my cat's name.
User avatar
Sammy_P
Rainbow SuperStar
Posts: 2787
Joined: Fri May 11, 2007 9:01 pm

Post by Sammy_P » Sat Mar 10, 2012 2:07 am

hoomdoom wrote:
ALSO

The following equation is wrong: 101 - 102 = 1

Move one numeral to make it correct.
Already posted that.

101 - 10^2 = 1
User avatar
hoomdoom
Rainbow Keeper
Posts: 321
Joined: Fri Feb 24, 2012 11:23 pm

Post by hoomdoom » Sat Mar 10, 2012 2:13 am

Sammy_P wrote:
hoomdoom wrote:
ALSO

The following equation is wrong: 101 - 102 = 1

Move one numeral to make it correct.
Already posted that.

101 - 10^2 = 1
Oh, sorry. :oops:
Hoomdoom is my cat's name.
User avatar
Technos72
Rainbow MegaStar
Posts: 3227
Joined: Thu Nov 26, 2009 12:20 am

Post by Technos72 » Sat Mar 10, 2012 2:21 am

I was sitting staring the 101 - 102 puzzle. I did not know ^ was a numeral, or is it not?

This is an example of what I'm talking about: Move one number to make this problem make sense (yeah it's easy the way I think it)

51 - 110 = 4
Image
MyNameIsKooky
Rainbow Spirit Master
Posts: 9495
Joined: Mon Dec 01, 2008 10:18 pm

Post by MyNameIsKooky » Sat Mar 10, 2012 2:23 am

hoomdoom wrote:What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?
5±9?
User avatar
hoomdoom
Rainbow Keeper
Posts: 321
Joined: Fri Feb 24, 2012 11:23 pm

Post by hoomdoom » Sat Mar 10, 2012 2:24 am

MyNameIsKooky wrote:
hoomdoom wrote:What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?
5±9?
Nope.

HINT: There are two answers (That I know of)
Hoomdoom is my cat's name.
User avatar
StinkerSquad01
Rainbow AllStar
Posts: 4237
Joined: Mon Aug 09, 2010 3:39 am

Post by StinkerSquad01 » Sat Mar 10, 2012 2:26 am

EDIT: Messed up the math. I know the answer, but I'm not going to say it.
@minimus#2048
message me on discord, won't you?
MyNameIsKooky
Rainbow Spirit Master
Posts: 9495
Joined: Mon Dec 01, 2008 10:18 pm

Post by MyNameIsKooky » Sat Mar 10, 2012 2:36 am

A 4th-root symbol.
User avatar
StinkerSquad01
Rainbow AllStar
Posts: 4237
Joined: Mon Aug 09, 2010 3:39 am

Post by StinkerSquad01 » Sat Mar 10, 2012 2:38 am

MyNameIsKooky wrote:A 4th-root symbol.
That does indeed work, giving the answer of 8.6602540378443864676372317075294. Neat.
@minimus#2048
message me on discord, won't you?
Post Reply