Need help with physics question

Everything non-WOK related should go in here.

Moderators: Duke, trewqh, korexus, Egbert

User avatar
korexus
Moderator
Moderator
Posts: 2827
Joined: Tue Nov 12, 2002 8:00 am
Location: Reading
Contact:

Post by korexus » Tue Apr 12, 2005 11:35 am

Sorry Nick, but you're absolutely wrong...

The turd will accelerate in a downwards direction, but this won't cause it to decelrate horizontally...

Common practice with set ups like this is to divide the forces into components in one direction and components in a perpendicular direction. For this we may as well take down and forward.

Acting downwards, we have an intial velocity of 0, some small (?) force from Duke's backside and mass * gravity. We pull out N-II and say that the ecceleration downwards is ~9.81 meters per second per second. We can also factor in air resistance vertically if you like, but we'd have to measure the turd. Regardless, simple trigonometry shows that the effect of these forces in the horizontal direction is F * cos(90) for some F. Which will always come out as 0.

Acting forwards the turd has an initial velocity of 50 km/h there is no air resistance acting on it as the air in the coach is also moving at 50 km/h. (If it didn't you'd feel a lot of breeze every time you drove your car.) Any collision with the air through brownian motion will be the same in each direction, so we can ignore it. Meaning the Turd will drop exactly vertically beneath Duke.

If you want the total velocity, it will be SQRT(50*50 + v*v) at an angle of inverseTAN (v/50) below horizontal where v is the downward velocity at that time.

If you want to calculate v at a certain point, you can get it by v= SQRT (2 * 9.81 * s) where s is the distance it's dropped so far in meters. Neglecting air resistance and force from Duke's ass.


Duke, if you really want to confuse the guy. Ask him which direction the bus is travelling. Believe it or not, that will have an effect! :P


korexus.
With Great Power comes Great Irritability

User avatar
Donut
Warlord
Warlord
Posts: 1041
Joined: Fri Jun 27, 2003 7:00 am
Location: Brew Town, WI; USA - BoV
Contact:

Post by Donut » Tue Apr 12, 2005 2:03 pm

He's right Nick. The horizontal and vertical components of a velocity problem such as we have here are completely independent; ie. Gravity does not effect horizontal motion...

Donut
The scars remind us that the past is real.

User avatar
Dameon
Moderator
Moderator
Posts: 1056
Joined: Tue Sep 03, 2002 7:00 am
Location: Valn Ohtar Chapterhouse

Post by Dameon » Wed Apr 13, 2005 1:19 am

Just because I wanted this argument to end, I asked my friend, who has not one but three degress in physics (bachelor's, masters, and PhD) to take a shot at answering. He does agree that the turd would be moving at 50 MPH (sorry Duke), and I see the sense to it although I still personally believe there would be a minute difference in velocities. He also states that for the bird question, the overall mass of the plane stays the same, for the reasons Korexus listed in re to the birds displacement of the air. In re to the spit question, that's a little more fuzzy because it involves some physiology in re to the technique of spitting, so he didn't have strong opinion on it. Finally, the ants would definetley win by sheer numbers.

I really don't see how your "friend" could argue a PhD in physics, so that basically means you both have one right with two undecided. Maybe you need another? I do have a handy resource here to make sure you get the right answer, Duke. :lol:
"A Knight is sworn to valor, his heart knows only virtue, his blade defends the helpless, his might upholds the weak, his word speaks only truth, his wrath outdoes the wicked."

User avatar
korexus
Moderator
Moderator
Posts: 2827
Joined: Tue Nov 12, 2002 8:00 am
Location: Reading
Contact:

Post by korexus » Wed Apr 13, 2005 10:24 am

Just because I don't want this argument to end (:P) back to the ants!

I'd like to point you all to an article in National Geographic that I just happened to stumble across.

http://news.nationalgeographic.com/news ... _ants.html

Basically it explains how a species of wasp, Ichneumon eumerus can produce chemicals which cause contaminated ants to be attacked by the uncontaminated ones. If your wasps have access to such chemical weapons, I would like to change my answer. Even one wasp would have a good shot at taking down a nest of ants given that sort of firepower!


Thanks, Protput I'll have that crown back now. :grinking:
With Great Power comes Great Irritability

User avatar
Duke
Moderator
Moderator
Posts: 1699
Joined: Wed Sep 04, 2002 7:00 am
Location: Sweden, Valn Ohtar

Post by Duke » Wed Apr 13, 2005 12:58 pm

I KNEW the wasps would pull through!!!

Anyway, we have cosidered the competition a tie and called it off and are working out a new way to settle it. It will be far better then this one and we will include the aspect of using each others "contacts". Good for me since I have within my grasp the most depraved minds in human history. Even if he has the smartest people that Hull has to offer in his staff I still have an edge since I also have the best NAP breakers the military world ever produced so I can weasel my way out of any deal and still come out on top. 8)
First one here, last one to leave.

User avatar
Hannibal
Commander
Commander
Posts: 886
Joined: Sun Sep 21, 2003 7:00 am
Location: London and The Vulkings Clan.............(started in Valn Ohtar, then jointly founded The Vulkings)

Post by Hannibal » Wed Apr 13, 2005 3:14 pm

As for the bees versus ants question ...... it obviously, as usual, depends on diplomacy ....... who makes the best deal with the neighbouring human and spiny-ant-eater players ..... 8)

Han
There are two ways to write: Short-hand, and Long-Han'ed. ~ Han

"If you can keep your head when all about you are losing theirs"......... it's probably just that you're the last person to appreciate the enormity of the catastrophe about to

User avatar
Donut
Warlord
Warlord
Posts: 1041
Joined: Fri Jun 27, 2003 7:00 am
Location: Brew Town, WI; USA - BoV
Contact:

Post by Donut » Wed Apr 13, 2005 3:28 pm

HAHAHAHAAHHAHAHA.... I love it.

Oh Korexus... wrong n00b you're talking to :P Keep'em straight.

Donut
The scars remind us that the past is real.

User avatar
Duke
Moderator
Moderator
Posts: 1699
Joined: Wed Sep 04, 2002 7:00 am
Location: Sweden, Valn Ohtar

Post by Duke » Wed Apr 13, 2005 4:19 pm

Ok, me and Hullie have a new deal.

I send him 3 questions. He sends me 3 questions. We both take a photo with the answers to the questions beside a newspaper with todays date on it. That way there is a definite correct answer (like in the ants vs wasps situation).

He got these questions:

1. Which Swedish actor had a tiny mustach and is mostly known for doing humours things but has also played in an Ingmar Bergman movie?

2. Which Swedish hockeyplayer has had most number of stiches made in his face (as far as the general public knows)

3. During the summer hockeycamp of Furudal in -89. What was my nickname?

Belive it or not, he accepted these questions. :shock: lol!!!!! Good luck with the third one :lol:

Here is mine:

1.When you have a insoluble substance (such as
calcium hydroxide)and add it with a weak acid or other weak electrolyte(such as acetic acid)would there even be a reaction;or would the two substances stay in their molecular form in the solution and never react?

2. Who would win a war between the US and the rest of the entire world. (you must take in effect that a lot of those countries doesnt cooperate at all)

3. Are you created by your history or is your history what you are created of?

I have no clue about any of those but I am sure that at least number 1 will be solved by someone (looks at Nick). And we have had the US vs. The world thread soooo many times here so we simply have to settle this now :wink:

The last one is simply stupid. Any philosophers in the group?
First one here, last one to leave.

User avatar
Hannibal
Commander
Commander
Posts: 886
Joined: Sun Sep 21, 2003 7:00 am
Location: London and The Vulkings Clan.............(started in Valn Ohtar, then jointly founded The Vulkings)

Post by Hannibal » Wed Apr 13, 2005 4:29 pm

Duke wrote:

Here is mine:

3. Are you created by your history or is your history what you are created of?


The last one is simply stupid. Any philosophers in the group?
Hmmmm. Yes I'm a philosopher, an adherent of Unwahrscheinlichstein.

But I'm also a grammarian. These two are identical options. He is teasing you to see whether you spot that both options are the same in meaning?

Han
There are two ways to write: Short-hand, and Long-Han'ed. ~ Han

"If you can keep your head when all about you are losing theirs"......... it's probably just that you're the last person to appreciate the enormity of the catastrophe about to

User avatar
TK
Trooper
Trooper
Posts: 209
Joined: Thu Aug 05, 2004 7:00 am

Post by TK » Wed Apr 13, 2005 4:32 pm

Duke wrote:1.When you have a insoluble substance (such as
calcium hydroxide)and add it with a weak acid or other weak electrolyte(such as acetic acid)would there even be a reaction;or would the two substances stay in their molecular form in the solution and never react?
Calcium hydroxide reacts with hydrochloric acid to give calcium chloride and water.

This is a typical high school chemistry lesson - finding the concentration of limewater.

I am sure Nick will shed further light (if he really IS a chemist :wink: ).

User avatar
Hannibal
Commander
Commander
Posts: 886
Joined: Sun Sep 21, 2003 7:00 am
Location: London and The Vulkings Clan.............(started in Valn Ohtar, then jointly founded The Vulkings)

Post by Hannibal » Wed Apr 13, 2005 4:43 pm

If he's trying to fox you with quasi-philosophical questions, then hit him with this:

Heisenberg's Uncertainty Principle shows that you cannot be precise about both the question and the answer at the same time ......the more you fix the one, the less fixable the other one is. That should defeat all of Hull with several parts of the rest of Yorkshire to spare .....

Han
There are two ways to write: Short-hand, and Long-Han'ed. ~ Han

"If you can keep your head when all about you are losing theirs"......... it's probably just that you're the last person to appreciate the enormity of the catastrophe about to

User avatar
Duke
Moderator
Moderator
Posts: 1699
Joined: Wed Sep 04, 2002 7:00 am
Location: Sweden, Valn Ohtar

Post by Duke » Wed Apr 13, 2005 4:45 pm

Typo.

I copied and pasted the first one and wrote the other two from memory.

Are you creating your history or is your history creating you?
First one here, last one to leave.

User avatar
Brykovian
Moderator
Moderator
Posts: 1045
Joined: Tue Sep 03, 2002 7:00 am
Location: Minneapolis, MN USA ... Clan: Scholars
Contact:

Post by Brykovian » Wed Apr 13, 2005 4:54 pm

I'll take a Bryk-like* shot at these ...
1.When you have a insoluble substance (such as
calcium hydroxide)and add it with a weak acid or other weak electrolyte(such as acetic acid)would there even be a reaction;or would the two substances stay in their molecular form in the solution and never react?
I'm guessing that "insoluble" would assume "in water" ... you mix any basic material with any acidic material and you will get a reaction -- resulting in a combination of the two materials, plus some water ... just like what TK explained for those two particular things.
2. Who would win a war between the US and the rest of the entire world. (you must take in effect that a lot of those countries doesnt cooperate at all)
If the war saw the use of nuclear weapons, then the answer is "nobody" ... if everything stayed conventional (no NBC's), then the "rest of the world" wins based upon sheer numbers.
3. Are you created by your history or is your history what you are created of?
It all depends on the perspective. From your own point of view, you are creating your history by acting in the now and having it slip into the past. From anyone else looking at you, your history creates you in a way, because learning and understanding your past is really the only way others can get to "know" you.

-Bryk

* - Bryk-like: completely making it up, with no references to or reliance on anything of actual merit or authority
Matt Worden Games ... Gem Raider, DareBase, Castle Danger, Keeps & Moats Chess

User avatar
Xechortariaste
Recruit
Recruit
Posts: 80
Joined: Sun Feb 27, 2005 8:00 am
Location: Akron, Ohio, USA -- BOT

Post by Xechortariaste » Wed Apr 13, 2005 8:15 pm

korexus wrote:Just because I don't want this argument to end (:P) back to the ants!

I'd like to point you all to an article in National Geographic that I just happened to stumble across.

http://news.nationalgeographic.com/news ... _ants.html

Basically it explains how a species of wasp, Ichneumon eumerus can produce chemicals which cause contaminated ants to be attacked by the uncontaminated ones. If your wasps have access to such chemical weapons, I would like to change my answer. Even one wasp would have a good shot at taking down a nest of ants given that sort of firepower!


Thanks, Protput I'll have that crown back now. :grinking:
Wow... very impressive. Chemical warfare on an insectoid level... I never would have thought of it. Of course, the article only mentions the ant species Myrmica schencki, which as far as I can tell, is not a fire ant. However, it seems to be close enough to the Myrmica rubra, or the European fire ant, for the chemicals to still work. If anyone over there in Europe feels like catching some Ichneumon eumerus and some of these ants, we can confirm the hypothesis. :P Since scientists are considering possible applications as insecticide, it's probably reasonable to suppose the chemicals would work on most ants. Very impressive, korexus. Even though you did get my name wrong :roll:, the crown is yours.

Next you're gonna tell me a certain species of ant has developed nuclear weapons...

Anyway, let me try my hand at the new questions.... We actually were doing something very similar in my chemistry class today. I wasn't really paying attention (who would when you can figure out your orders for a WOK game instead?), but it seems to me that CaOH and C2H4O2 (acetic acid) would, as has been said, yield water and some form of salt. The only thing that causes me pause is that it's insoluble (does not dissolve in water). But, after looking around a bit, it seems that even insoluble bases will react with an acid to form water, they just won't then be carried away by the water the reaction creates, and will probably leave a salty residue of some sort.

Question two... At first I agreed with Bryk, in that if the war was nuclear (and I think we here in the US would use those nukes before letting everyone else invade us), there would be no winners. But a nuclear war would only destroy this world... any nation which could get a fair number of people off this world would survive, while the war itself and the resulting nuclear winter would kill everyone still on the planet. Therefore, in an all-out nuclear war, the nation with the best space program wins. At the present time, the only nation that has any real ability to send people into space is Russia, and a lot of their space program money comes from the US anyway. Even once the shuttle starts flying again, the shuttle never really even goes to space. That, however, is right now. Now, admittedly, a lot of the world isn't too happy with the US right now, but it's not quite to the point where the whole friggin world would declare war on the US. We've still got some allies who at the very least would remain neutral. Once you factor in enough time for us to get them so angry they all uniformly declare war on us, plus enough time for the war to escalate to a nuclear level, I don't think our space program is going to have gone anywhere at all. But, right now there are a number of private companies beginning to open up the space market, and in the next few years they will be able to offer space flights to very, very rich people. That means that by the time the world blows itself up, a few select CEOs and investors and maybe some Arabic oil kings would be able to secure passage off the Earth. Since these companies are largely American, the USA wins. :lol:

I am going to go fix myself a sandwich, and I will contemplate Question 3 later.

User avatar
korexus
Moderator
Moderator
Posts: 2827
Joined: Tue Nov 12, 2002 8:00 am
Location: Reading
Contact:

Post by korexus » Wed Apr 13, 2005 8:42 pm

Xechortariaste wrote: Very impressive, korexus. Even though you did get my name wrong :roll:, the crown is yours.
You young 'uns all look alike to me :wink: anyway, Protput was easier to spell! :lol:
Xechortariaste wrote: Next you're gonna tell me a certain species of ant has developed nuclear weapons...
Can't find any yet, but you never know. Here's a question though: If the wasps had nuclear weapons, would they work on the ants? I'm told cockroaches can survive a nuclear blast, could ants?

For the new questions,
Chemistry: It's been far too long, other people are doing fine here so I don't care! :P

War: if we were to blow up the world, America as the only superpower would have the highest score and would therefore win the game, but if we didn't blow up the world I'm going with Bryk on rest of the world by weight of numbers.

Philosphy: 'yes'



korexus.
With Great Power comes Great Irritability

User avatar
Xechortariaste
Recruit
Recruit
Posts: 80
Joined: Sun Feb 27, 2005 8:00 am
Location: Akron, Ohio, USA -- BOT

Post by Xechortariaste » Wed Apr 13, 2005 8:49 pm

Duke wrote:Are you creating your history or is your history creating you?
If we want to go back to the grammar... You are currently creating your history. Your history already has created you. By definition, history is in the past, and cannot be acting in the present.

User avatar
Dameon
Moderator
Moderator
Posts: 1056
Joined: Tue Sep 03, 2002 7:00 am
Location: Valn Ohtar Chapterhouse

Post by Dameon » Thu Apr 14, 2005 1:42 am

Duke wrote:Ok, me and Hullie have a new deal.

1.When you have a insoluble substance (such as
calcium hydroxide)and add it with a weak acid or other weak electrolyte(such as acetic acid)would there even be a reaction;or would the two substances stay in their molecular form in the solution and never react?
Ok, I can answer that. Disclaimer though; the following answer is only valid if you are specifically talking about acid/base reactions, which you are given the chemicals named above. Other "insoulble" (and I use that term lightly for various reasons) chemicals would have different reactions with a weak acid depending on their own relative acidic or basic qualities (or lack thereof, for that matter) For the chemicals named above though.....

One thing you have to understand about basic acid/base reactions is that whenever you mix an acid and a base there's always some kind of reaction. It may not be something that is visible, but it's usually measurable using the right equipment. Also, in almost all acid/base reactions the reaction also works in reverse. How much in reverse depends on Keq, the equilibrium constant in the reaction. For instance, if you mix a strong acid and strong base, the Keq is very large (much greater than 1) so there is almost no reverse reaction. If you mix weak acids and bases, the Keq could be a lot closer to 1, meaning that the reverse reaction occurs almost as much as the forward reaction, giving much less of an overall effect. (Although the reaction still proceeds in general, as long as the Keq is anything above 1). You only get no reaction if the Keq is less than 1, which in acid/base reactions never happens by definition. (The Lewis or Bronsted/Lowry definitions anyway, but I digress)

In your example, using the chemicals above, calcium hydroxide is a strong base (as are most group I and II hydroxides), and acetic acid is a weak acid. The solubility (in water or otherwise) of the INITIAL chemicals means little if anything in the actual reaction. All this boils down to is a strong base/weak acid reaction, which will produce some water and the accomanying chemical, in this case calcium acetate. NOW solubility comes into play; if calcium acetate is soluble you won't see any calcium acetate salt appearing, although it'd still be in the solution. You might still have some unreacted calcium hyrdoxide salt sitting around in the bottom of your beaker, too, depending on how much acetic acid you put in. You'd need a much higher molar solution of acetic acid (or much more in general volume) in ratio to the calcium hydroxide to react all of it.

I could go into even more detail regarding water, it's acidic/basic tendencies, general acid/base definitions, and the like, but I think your get the point. Bottom line, yes, there will be a reaction. Water will form, calcium acetate will form, and there may or may not be some calcium hydroxide salt left at the end depending on the molarity/volume of the acetic acid you start with. 8)
"A Knight is sworn to valor, his heart knows only virtue, his blade defends the helpless, his might upholds the weak, his word speaks only truth, his wrath outdoes the wicked."

User avatar
Duke
Moderator
Moderator
Posts: 1699
Joined: Wed Sep 04, 2002 7:00 am
Location: Sweden, Valn Ohtar

Post by Duke » Thu Apr 14, 2005 5:28 am

I knew you guys would pull out a huge explanation to Q1 :)

Anyone wants a shot at my question?

Oh, and being the persons you are :roll: I am surpriced no one has seen the trick I am pulling. I am suppoused to take a picture of a newspaper with "todays" (that was 2 days ago) date on it and a note with the correct answer "so you cant cheat". He sends me his answers and I send him the photo with the correct ones.

Now, how many of you thinks I have saved that paper and will be writing the note and taking the picture after I got his mail and how many of you thinks I play this fair :wink:
.
.
:shock:
How many thinks he is doing the same thing??
First one here, last one to leave.

User avatar
trewqh
Moderator
Moderator
Posts: 1877
Joined: Mon Dec 09, 2002 8:00 am
Location: Bialystok, Poland clan: The Vulkings

Post by trewqh » Thu Apr 14, 2005 8:41 am

Duke wrote:Are you creating your history or is your history creating you?
Assuming that 'creating' here means influencing the way something is or appears:

1. No. One is able to influence events that will be perceived as history in the future (but presently those events cannot be called history, yet).

2. Yes. Simple example: decisions of some previous government of a country influence the present economics. The present state of economics of a country influences it's citizens. (Including the 'you' from the question)

Assuming that 'creating' means putting together from the very beginning to finish with a complete... something :P, then neither of the questions is true.

8)

trewqh

User avatar
Duke
Moderator
Moderator
Posts: 1699
Joined: Wed Sep 04, 2002 7:00 am
Location: Sweden, Valn Ohtar

Post by Duke » Thu Apr 14, 2005 6:15 pm

I thought you were on the road with your band.

:drummer: :irock: :rockband: :rockband: :pianoman:
First one here, last one to leave.

Post Reply