BrainDen.com - Brain Teasers

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For number 5

Temperature is a measurement of the amount of molecular kinetic energy in a substance. To say that it is twice as cold is to say that there is half as much kinetic energy. At 0 Kelvin there is no kinetic energy so it is a useful tool for directly measuring the amount of molecular kinetic energy. If it is 0 degrees Fahrenheit then it is 255 Kelvin. If it is twice as cold, it would therefore be 127.5 Kelvin or -230 degrees Fahrenheit. I certainly hope the weatherman was wrong.

As for number 4, I have another question. If the girl were to go back and kill her father before she was born, and her mother remarried, would she be born as someone else or would someone else be born?

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#7

i think that the light from your headlight would still travel faster than the car. because the headlight is part of the car. the initial velocity of the light is the speed of light, so its like the light is being catapulted by your speed.

you would be get past the headlight if the source of the light is slower than yours.

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Number one, time would stop...

(they both reach infinite speed and time slows to a stop) LOL

Yog

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7. What happens if you are in a car going the speed of light and you turn your headlights on?

Nothing, at the speed of light I have infinite mass and cannot move to turn the lights on... LOL

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1 - let us conjour in our imaginations something which can't exist and then conjour something else which also can't exist - why are we surprised if two things which individually can't exist conflict with each other. I can conjour things which can't exist all day long and many of them will be in conflict with each other. More fundamentally they are in conflict with reality. Isn't this the beauty of human imagination, and its greatest danger.

2 - same answer - why are we surprised when we conjour something which is in conflict with reality to find that it is in conflict with reality.

3 - are we surprised to find that we can close a logic loop ? hardly.

4 - see answer 1 - imagine an object in conflict with reality and then state the conflict in a different manner - no problem just the flexibility of imagination.

5 - this is just an apparent paradox - not a real one - the implicit information is that 0 is cold - otherwise tommorrow could not be be twice as cold. The listener knows how cold today is - specifically how much colder than some expected norm - lets say the normal temperature for the time of year to a normal resident of the region is 10 degrees - then twice as cold is twice as far below the norm as today is - or -10 in our example.

6 - see 3 - we can easily lock ourselves in a loop - but it's no paradox.

7 - this is not not a paradox - the speed of light is a limit relative to another object (or indeed relative to all other objects at the same time) - so from the point of view of the car the light from the headlights moves away normally. Now consider this - the universe is an immensely vast space, containing an immense number of objects - these objects have varying speeds relative to my car - some of them may be travelling at speeds approaching the speed of light relative to my car - and I devoutly hope these objects are at a very great distance from my car - so this evening when I turn on my lights I am carrying out this test - and lo and behold despite my car's travelling at a speed aproaching that of light relative to some unknown but extant object my lights work just like yesterday - which isn't surprising as yesterday my car was also travelling at speeds approaching that of light relative to some other objects - now the real question is whether there are more today than there were yesterday.

8 - see answer 1 - imagine two things which can't exist - so why be surprised to find them in conflict with each other.

JSL

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I love the answers to #1 which say only one can exist, not both. This is the classic trick that leads to the chicken and egg problem.

The key is to deny the existence of both - not just one.

In the same way the chicken and egg question is answered by the questioning the inherent flaw. The question is not which came first - the point is that they are a single object - a chicken in a reality without chicken's eggs is no more possible than a chicken's egg in a reality without chickens.

Note I'm avoiding the trivial dinosaur egg answers etc. which just sidestep the challenge rather than face it.

JSL

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you can join the chicken vs. egg discussion here

I like WB's definitions

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So do I, and thank you - I suspected it would be somewhere in here.

JSL

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1. The bullet would miss

2. Yes, but he would drown eternally

3. Yes, but I would fail the mission

4. Maybe this is how people disappear

5. -32.0000001 degrees fahrenheit

7. Nothing, until you slow down

8. God does not need to pick up stones, he gets someone else to do it for him

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#7...if you are going at a certain speed, and then you project an object (yes light is an object) the object will be shot out at a faster rate then the rate you are going...so if your going the speed of light, and you turn your headlights on, the headlights will be shot going the speed of light at the speed of light, which in theory can not happen but can logically, then the light would be going a whole speed of light faster then the car, allowing it to be ahead of the car normally. Cannot be proven yet, but still my theory. Just like when your going 200 mph in space..then shoot something out into space..that object will be going faster then 200 mph. just like the light would

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For the most part, these are meant to be paradoxes so it's easy to say that the statements and questions are invalid in the first place and avoid the conundrum altogether. But I like the responses that assume that the given statements are true above all (because God said so, it was a proven scientific observation, or whatever convinces you), or at least they try to keep them valid and intact as much as possible. Anyway, I have thoroughly enjoyed reading the incredible creativity displayed by many of the responses given in this sense - excellent stuff! And I thank you all for the good read!

So I thought I'd join the fun and take my own stab at these. I agree with many of previous responses, but I haven't seen some of mine posted at all, so I hope I'm bringing something new to the table..

Apologies in advance for the long-winded answers. Just trying to make the details clear (but I may have actually made things worse)

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1. Let's say (hypothetically) there is a bullet, which can shoot through any barrier. Let's say there is also an absolutely bullet-proof armour, and nothing gets through it. What will happen, if such bullet hits such armour?

Again, many will say that the correct answer is that neither can exist and that these statements are lies. But I don't like these types of response, so...

(I) If these do in fact exist, then I propose they're both be made of the same material. It then becomes a matter of the material's properties when meeting the same. Do they annihilate themselves in a nuclear explosion of some kind? Do they just dent/damage each other (change shape) in some way? OR, since they're both impenetrable, do they simply deflect from each other, per equal and opposite force laws, without sustaining any damage? (which can include both of them standing still under some constant forces or no further force exerted upon them after impact) Perhaps their thickness, speed, angle of impact, etc. is the determining factor?

(II) Not necessarily. After careful consideration, I have to conclude that the armor must be a black hole and the bullet is yet another!

If they meet, they will fuse together and in essence become one. However, since the bullet cannot be destroyed, it will infinitely continue to attempt to penetrate the singularity, while the armor will infinitely continue to "block" it because the bullet will never reach it's center. Yes, they are still capable of doing what they were designed to do as stated, but I wouldn't hold my breath waiting for the results of this particular experiment. This satisfies all the given conditions, including that they both can exist. Problem solved.

2. Can a man drown in the fountain of eternal life?

No. You cannot "drown" because that would mean death (dictionary and biological meaning), which is impossible if such a fountain were to indeed exist. Thus, the only possible things that can happen when submerging someone under this fountain's "water", for an indefinite amount of time are:

(I) You would suddenly be able to breath under this fountain's "water" like some divine fish.

(II) You no longer would need to breath to stay alive, again, like some divine fish.

Some may argue that you do indeed drown and die, but that you're taken to a different type of "eternal life". However, if you're dead in the physical one, then the fountain fails for "life as we know it" and becomes just another great big lie!

3. Your mission is to not accept the mission. Do you accept?

No, I do not.

(I) If you accept, then you fail the mission of not accepting it - you'd be a loser and a sucker if you did.

(II) If you don't accept the mission, then it doesn't apply to you! I mean should you bother accomplishing missions you don't accept? Does anyone? This way it won't matter what the mission was is in the first place! There'd simply be no mission to worry about. There'd be no mission to succeed or fail at.

4. This girl goes into the past and kills her Grandmother. Since her Grandmother is dead the girl was never born, if she was never born she never killed her grandmother and she was born.

First, unless otherwise stated, we must assume that the girl kills her "bloodline" grandmother, not some surrogate grandmother or whatever, because when she does kill her, the girl prevents her own birth. These are the givens. Second, parallel universes and multiple timelines can solve any time paradox, but what if those didn't exist? To me, it's more challenging with one universe and one timeline, so..

(I) It may still be possible for this to happen. Even though the girl had been alive once, we'd never know it because she would've changed history to one where she didn't exist anymore, the instant she killed her grandma. All we'd have on record is her grandmother's unexplained death! The event happened and simply altered the only timeline there was, from that moment on - knowledge of her existence forever lost. Events like this could happen all the time and we'd never know it - we'd simply only know the current timeline after the changes. We'd be convinced that the history we know had always been that way, even though events like this may have changed it a thousand times! The history books will always have accounted for these events since the time of their occurrence. In your reality, the non-time-traveler, they'd always be "up-to-date". Changing the past would also change what you think you remember it to be! You'd just never know it.

(II) In all honesty though, I don't really believe this. I believe that either time travel is not possible, or that if it is, you can only do so as an non-influencing observer, incapable of altering it. You'd only be able to "look" through this "time window", not only unable to affect anything you see, but you wouldn't be seen either. Perhaps there are thousands of time travelers observing the past at this very moment! Maybe that's what they do for vacation, or for historical accounting, in the future. In fact, at this very moment, I'm looking at what you did yesterday!

5. If the temperature this morning is 0 degrees and the Weather Channel says, "it will be twice as cold tomorrow,".... What will the temperature be?

(I) The weatherman cannot be talking Kelvin degrees, even if he was referring to the weather on some icy planet, because nothing can be colder than absolute zero - there can be no "twice as cold" on the Kelvin scale.

(II) The "Weather Channel" exists in the US, UK, Australia and maybe other English-speaking countries (the report's language), so it can be referring to either Fahrenheit or Celsius degrees - there's no way to know for sure.

(III) Temperature refers to how much heat, or lack of, there is. So "twice as cold" also means "half the heat". Without any given reference to compare to, we can try calculating what is meant using the Kelvin scale; which we already know he's not talking about. But if you said that scientifically there was no other choice, then you'd have either:

-----> 0 F deg. = 255.372 K deg / 2 = 127.6861 K deg. = -229.835 F deg.

-----> 0 C deg. = 273.150 K deg / 2 = 136.5750 K deg. = -136.575 C deg.

Which are both absurd in light of the fact that it's being reported on the "Weather Channel" and that it'd be, for all practical purposes, useless to anyone, and so there'd be no need to report the weather to begin with. But there was a report, so this cannot be the case.

Conclusion: Based on the unreliable information given, you cannot know what tomorrow's the temperature will be.

The Weather Channel has made a mistake and reported nonsense this time. You should ignore the report; which shouldn't be too hard to do as they've made many errors in the past, even when the reporting actually did make sense.

6. Answer truthfully (yes or no) to the following question: Will the next word you say be no?

First, as I stated in the beginning, I'll assume that you'd be killed if you didn't answer it, or for others that "God said so", or whatever way you can be "forced" to do so. Basically, answer or die!

(I)The word "say" means expressing something in spoken or written words, OR by other means, artistic or otherwise - look it up. So typing your answer, having your lawyer respond on your behalf, etc. won't get you out of it so easily.

(II) If that's the case, then you can "say" whatever you like, but you cannot be "truthful" at the same time. But what's the big deal if you weren't truthful? There is none! It appears the problem then falls on the one who asked. Hey, it's their fault so they should be the one's to have to deal with it what your response means.

7. What happens if you are in a car going the speed of light and you turn your headlights on?

(I) According to special relativity, it is impossible for any material object to go at the speed of light. Thus, the car could only go at near the speed of light at best, which is not valid since you're specifically given the "fact" that you're going at the speed of light. This can only mean that you and the car must be made 100% of some type of electro-magnetic wave, visible light or otherwise, that can go at this speed.

(II) If you and the car were made of, and able to exist as, this "wave" form, then:

- (a) If you're made of "visible" light then the cells in your eyes would only see light all the time regardless of the state of the headlights. You'd be blinded by the very light you and your car are made of. Everything including the headlights would already be "on".

- (B) If you're made of some other "wave" and the headlights still emitted "visible" light, you still would not see them or the light they emit. Due to time-dilation, the faster you go the slower time moves. At near the speed of light, time almost stops. At the speed of light it would, and you'd never get to turn the headlights on in the first place, or do anything else for that matter.

(III) If you rewrote the question to say, travelling at "near" light speed, and time didn't stop completely, the light from the headlights would travel away from you at the speed of light - which, according to Special Relativity, is always the same for ALL observers. Time is what's changed to compensate. So yes, you'd see this light reflected off an object and back into your eyes (which is what is meant by "see"), but to you it would seem to take an eternity for the light to reach said object because of time-dilation. The good news is that once it does reach and reflect back, you'd see it almost instantly, but only after your almost-eternal waiting period. But let's not forget that your astronomical wait time would take place in less than a nanosecond to anyone not traveling with you. Or something like that.

8. I conclude with this challenge:

Let the God Almighty create a stone, which he can not pick up (is not capable of lifting)!

Since "not capable of lifting" can be referring to either not having the strength to do so, or there being a rule or something blocking the ability to do so, it would seems there could be at least two possible answers. But there are not:

(I) All those that say he simply refuses to, have forgotten that just because he says he won't lift, doesn't mean he's "not capable of lifting" it. Whether he takes the form of a mouse or whatever, he is still God, so his powers are always with him regardless. If anything, he'd only be trying to lie about not being able to lift it, but we'd know better because he's "almighty" and never lies, especially to himself! And even if he makes such a rule for himself, he can never break it, because doing so means he failed to make such a stone. And if kept the promise, there'd forever be at least one thing he couldn't do, which would nullify his "almighty" title. But in the statement we're given that he IS God and "almighty", so this can't be the solution to his dilemma. Again, I don't want to invalidate anything if I can help it, so...

(II) In order to "lift" anything, there has to be something to lift it from, i.e. there has to be a gravitational force acting upon it. Others here have said that he can just make the universe one giant stone to accomplish the same task, i.e. there'd be nowhere to "lift to".

But I think it's simpler than that:

There are already countless celestial "stones" (asteroids, etc.) that are themselves the source of the gravitational force needed for any "lifting" to occur; and as such, in this setting, they are not the "lift-able" things themselves.

God has already created stones which no one, not even God himself, can lift!

Of course, being almighty, he can undo this by simply placing these types of "stones" on a greater source of gravitational force than their own, at will. Hey, for God, it should be as easy as 3.14159265358979323...

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yes, this took a good while to think about and write up.

btw, this is my 3rd post. I just discovered this site and I'm impressed to find so many diverse thinkers under one roof!

I never knew there were so many other freaks like myself out there.

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1. Let's say (hypothetically) there is a bullet, which can shoot through any barrier. Let's say there is also an absolutely bullet-proof armour, and nothing gets through it. What will happen, if such bullet hits such armour?

They both can exist at the same time. If the bullet hits the armour, it will not pierce it, it will simply push the armour forward until it is dragged down by gravity, or if it is in space, it will just go on for a very very long time. This doesn't break any rules does it?

----------------

Now playing: Laser Inc - Det Var En G?ng En F?gel

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1. Let's say (hypothetically) there is a bullet, which can shoot through any barrier. Let's say there is also an absolutely bullet-proof armour, and nothing gets through it. What will happen, if such bullet hits such armour?

They both can exist at the same time. If the bullet hits the armour, it will not pierce it, it will simply push the armour forward until it is dragged down by gravity, or if it is in space, it will just go on for a very very long time. This doesn't break any rules does it?

I take it you agree that they'd have to be made of the same material then(?)

But in your scenario, the armor doesn't protect you! If the bullet pushes the armor into you, you'd be crushed by your own armor (if there's anything behind in the direction of the bullet's trajectory). Or, if there isn't, then you and your armor would be sent flying out of place into deep space forever, or into some celestial body, with no apparent escape to your new dilemma! I guess that will be acceptable to some(?) So yes, the armor in your case may be impenetrable, but what good is it if it defeats the purpose? I mean, it's supposed to be armor, not a new method of travel or way to commit suicide.

But hiding behind a black hole (outside it's event horizon) will prevent you from getting crushed or being thrown out into deep space when any bullet comes at you. Actually, it's even better than that because it'll protect you from bullets coming too close to your "armor" from multiple directions (if they fall inside the incredibly wide event horizon). If they don't get sucked in, then the bullet will miss you by a huge distance anyway.

Anyway, I'm glad there's at least one other person that agrees that they can both exist.

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In number 8: of course God can for he can do anything he desires so he can and has set parameters he can not cross like. Can God tell a lie of course not for when he would it would be the truth. think about that

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As for the speed of light if an object could operate at the speed of light and turned o hte lights is would omitt a wave that would not supercide it. on the other hand the theory tha an object can not travel at the speed of light is a twist because particles so and have traveled faster like at Hiroshma when particles traveled at the speed of light squared and released tremendous energy

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the bullet and armor of penetrable and impenetrable abilities is nor a brain teasers but the two statements just cancel themselves out

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can a man or man with a womb ( woman) drown in a pool of eternal life: absolutely! Too much of anything will kill you. If you arrive at the pool just take a sip and see what it will be for our meaning of death is so much different than reality. Death has never meant to cease to exist for when a man dies his bones we find for thousands of years, so "Death" has always meant and will ever be "Separation" so if a man keeps on drinking the waters of eternal life No he will not cease to exist but will be separated from the body he now knows for he will continue to become more youthful in his mothers womb and then his father's loins then grand father's loins till the beginning of time where he will exist in the mind of his creator dead or separation yes cease too exist No

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as for the number four: we have not enough information to make this a parodox nor brain teaser for if the girl is twenty and go back ten years ans kills her grand mother she will not stop her birth-- but on the other hand if she stays in the past where she is existing we do n ot know if her existance would be altered and even if she travels back to the future since we have now accepted that time travel was relevent we know not whether her mother or father traveled back to undue her deed

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The answer to 3 Absolutly! I do not accept the mission

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The answer to number five is 0 if the question is about absolute zero which is 455 degrees below zero (which is s number to represent the absents of heat if the 0 is Fahrenheit or Celsius it is a figure that can be doubled or reduced by it's self. But then again the answer could not possibility be since scientifically there is no such thing as cold only a lack of heat

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1. They cannot be simultaneously true. Based on our own human misjudgments of what is "impenetrable" and "unstoppable," somebody would be proven wrong.

Alternatively, you could look at it as a question of what defines "nothing gets through it." Let's say that the bullet-proof armor is 1" thick. If the bullet hit the armor and penetrated it by 0.5", then the bullet will still have technically shot through the barrier, yet nothing will have gotten through the armor.

2. I am not sure about the fountain of eternal life and what you define its capabilities as, but he would be able to if the fountain granted everlasting life, as in freedom from the death of old age. If mortality still came into play, he still could drown. There is also the argument of what you consider "death," though that is a branch of theology that ironically even I don't want to get into.

3. You assume that you have to accept the mission. I would say no, you would not technically accept it. Then again, it comes down to the definition of "accept" (funny how it seems to come down to a definition, doesn't it?), as in would you have to give an outright "yes" or would you imply acceptance by rejection?

4. If a woman went back in time and killed her grandmother, then at the moment that she rendered her grandmother physically incapable of reproducing anymore children (don't twist that around, you perverts ), she would simply vanish into non-being. People say against that that if she never existed, then she could not have killed her grandmother in the first place, etc. etc. etc. I didn't say she never existed, I simply said she didn't after a certain period of time.

5. There's a scientific answer to that someone else already posted, and I thank them wholeheartedly for doing so.

6. Once again, you assume that the question has to be answered. However, in any other sense, it's a true paradox.

7. The light would remain in the pinpoint position of it's origin.

8. My dad couldn't accept the challenge and succeed. Congratulations.

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Paradox #8 can be approached from the science point of view, but you will only end up arguing or mistakenly believing you have proven the non existence of God. The fact is God does exist, whether you believe it or not, doesn't change that fact. The evidence is all around you. I know that doesnâ€™t appear to you as proof or evidence, if you are hung up on that we can discuss that further in another post.

So the only way I see to understand #8 is to understand, as best possibly, the nature of God. Many posters have hit upon his nature throughout this topic. The Bible is full of evidence of His nature. So with out getting into a theological discussion of God's Nature, suffice it to say that God's nature does not allow him to contradict himself. So the creation of a stone too heavy to lift is a contradiction. People get hung up on defining what God can do, and atheists love to say that if God can't do everything then therefore he is not God. Again a failure to understand the nature of God. If you would take time to understand His nature, paradox #8 is easily thought through.

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This an answer that applies well to stories, or narratives. Whether or not reality is a narrative is a theological and philosophical problem.

Assuming time and space are relative to the girls perspective, therefore time and space exist both within her memory, and outside of it:

The events must take place linearly, ie: A must lead to B, therefore A occurred before B, therefore B still exists in some form. The problem lies in the makeup of the time/space continuum. Consider instead, that space/time is malleable, and the only absolute progression is the series of events described- a meta-narrative form of space/time if you like. Therefore:

If the girl is capable of going back in time and killing her own grandmother, then she must first go back in time, then kill her grandmother.

To kill her grandmother she must still exist as her grandmother dies.

So:

Let us say that she leaves her present, then visits her grandmothers present. She kills her grandmother and still exists.

Perhaps she is no longer born.

So:

Her Present time (as it existed previous to her act) must therefore have changed. That does not mean she ceases to exist. If she were to return to her present she would find that a different set of circumstances had led to her existence. If she could return to her presence.

You could say that her previous present time would have to change.

But this is not so bad, since by killing her grandmother, she herself would have changed as a human being, why not her time? Of course since she is the sole observer of these set of events, (not counting an audience, or dare i say, author), she would be quite unable to ascertain whether or not she had become insane.

Perhaps then the time traveling paradox can be stated as:

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Let's say there is a bullet which can shoot through any barrier. Let's also say there is an absolutely bullet-proof armor which no object can penetrate. What will happen if such a bullet hits such an armor?

If this whole thing takes place within time, then perhaps the answer is; the bullet takes an infinite amount of time to pass through the armor.

The simpler explanation is to contest any of the definitions.

On a more metaphorical note, perhaps the bullet is death, and the armor is the whole of reality.

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