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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?

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

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

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.

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?

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

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

8. I conclude with this challenge:

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

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As for number 2, i believe it is actually the "fountain of youth" in which case he would drown and probably never decompose, in the context of the question however it depends on whether eternal life merely lets you live forever while still being able to be hurt, or protects you from all harm, or both.

As for number 5, it is simply a matter of taking the used form of measurement (whether Celsius, Kelvin, or Fahrenheit) and converting it to another find the usable temperature. Then if you have a negative number multiply by 2 if positive divide by 2... (mathematically and scientifically that is... i believe that in the end it would be much more technical beginning with how you would define cold and at what temperature however i am possibly looking to far into it with that...)

To number 7, the headlight will turn on yet it will be trapped at it's exact source so long as you go EXACTLY the speed of light any slower and it will be ahead of you.... the real question i believe should be:

"What happens if you are in a car going 'faster than' the speed of light and you turn your headlights on?"

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well for the fountain of youth #2....i know it it say YOUTH which means young so you'll stay young. but its not fountain of life. Drowning ion the fountain of youth doesn't mean you can't die young!^__^ shoot it does say eternal life!!!!!!!!

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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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Well, i've got more paradoxes from number 4.

If she goes back to the time when she was 3 years old, and kill her, what would happen?

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Well, i've got more paradoxes from number 4.

If she goes back to the time when she was 3 years old, and kill her, what would happen?

havent you guys ever seen family guy? killing yourself if you go back in time doesn't mean you don't exist in the future, it just means that there's no longer 2 existences of yourself

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8. I conclude with this challenge:

Let the God Almighty create a stone, which he can not pick up!

Not a problem. God creates a pebble and then declares "I shall never pick it up". He is capable of lifting it, but can not break his promise. Conditions met.

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#7 has an answer, and it is a cinch. If you are in the car going the speed of light, your headlights shoot away from you at the speed of light (since it's a constant, it can do nothing but) However, a bystander watching as you whoosh by will see your headlights not extending from the from of your car whatsoever. To him the light will be pooling in the headlights, otherwise it would be going faster then light. In this way C stays constant for all observers. Simple.

Oh, I left one thing out... As the car approaches the speed of light, it's mass approaches infinite, so the bystander gets hit by the car the instant he sees it, and doesn't have time to come to any terribly advanced thoughts about where the headlights are.

#5 is a problem with unrigorous language. There is no measure of 'twice as cold' We measure the warmth of things, not their coldness. Just as there is no twice as thin, or three times less wealthy. Where does the thinness scale start? at 300 lb? 800lb? With no concrete and finite starting place for the scale, the increments are indefinable, and multiplication cannot occur.

Switching from Fahrenheit to kelvin solves nothing, because there is a Fahrenheit equivalent for any temperature. The question is where and when is he measuring the first drop to 0, that he can double that drop again tomorrow. Is it twice as cold as yesterday? As 6 months ago? as ten minutes ago? The scale is not defined. It's not a conversion problem. Even if you did transfer to Kelvin and subtract half, you'd be subtracting a nominal amount only since the increments are of different size. It would be a meaningless exercise.

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Well, i've got more paradoxes from number 4.

If she goes back to the time when she was 3 years old, and kill her, what would happen?

havent you guys ever seen family guy? killing yourself if you go back in time doesn't mean you don't exist in the future, it just means that there's no longer 2 existences of yourself

this question, if possibe would cause a rift in time because once u killed ur grandmother u never existed meaning she never died meaning u were born to go back in time to kill her so time would be in an infinite loop forever always repeating the same space of time.

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#7 is a Steven Wright joke. I asked my chemistry teacher about it and he said, because of relativity, your headlights would turn on, as normal, and the light would come out at twice the speed of light.

However, the question is impossible anyways, because for something to go the speed of light, ALL of it's mass must be converted to energy. The spaceship wouldn't even exist anymore.

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if you go back in time and kill the father of the guy who invented the time machine you traveled in what would happen to you?

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The bullet and armor one is kinda retarded since it is impossible for both of them to exist simultaneously. If the bullet can pierce anything, the armor is not invincible. If the armor is invincible, the bullet cannot pierce any barrier. It is one or the other. Never both.

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#7 is a Steven Wright joke. I asked my chemistry teacher about it and he said, because of relativity, your headlights would turn on, as normal, and the light would come out at twice the speed of light.

However, the question is impossible anyways, because for something to go the speed of light, ALL of it's mass must be converted to energy. The spaceship wouldn't even exist anymore.

What grade of chemistry are you in? And why are you asking a chemistry teacher about a physics problem?

The speed of light is a constant. Light cannot ever travel at twice the speed of LIGHT. It's light! That's like asking what is the maximum amount a brick can weigh, and getting the response 'twice as much as a brick can' it makes no sense, and it doesn't answer the question!

Furthermore, converting mass to energy is what radioactive decay does, not acceleration. As a body approaches the speed of light it acquires MORE mass, approaching infinite; thus requiring approaching infinite energy to accelerate it further. That is why a car will never travel the speed of light, because it would require infinite energy to move infinite mass, not because it needs to convert its mass to energy.

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What grade of chemistry are you in? And why are you asking a chemistry teacher about a physics problem?

The speed of light is a constant. Light cannot ever travel at twice the speed of LIGHT. It's light! That's like asking what is the maximum amount a brick can weigh, and getting the response 'twice as much as a brick can' it makes no sense, and it doesn't answer the question!

Furthermore, converting mass to energy is what radioactive decay does, not acceleration. As a body approaches the speed of light it acquires MORE mass, approaching infinite; thus requiring approaching infinite energy to accelerate it further. That is why a car will never travel the speed of light, because it would require infinite energy to move infinite mass, not because it needs to convert its mass to energy.

Actually, I made the whole thing up since I knew somebody was bound to spaz out about it. He actually said the same thing you did, but that's no fun. I think burning a hole in space time is waaaaaayyyy cooler. BTW, he teaches physics too. Thanks for the brief entertainment.

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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?

Unstoppable force meets immovable object, huh? As was already mentioned, you can't have both. One of them would be proved untrue when the 2 met.

2. Can a man drown in the fountain of eternal life? No, but he could remain eternally underwater in agony -- it isn't the fountain of eternal PERFECT life, is it?

3. Your mission is to not accept the mission. Do you accept? Doesn't matter, does it? -- there is no real mission. Accepting it means you don't accept it and Not accepting it means you inadvertently accepted it. Whoever gave you the mission is trying to distract you from something

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. Not enough information here ... the ASSUMPTION is the girl went back to a time before she was born ... but it doesn't say that, does it? So say the girl just goes back to yesterday & kills her grandmother -- then it wouldn't affect the girl being born at all. Otherwise, it depends on what you believe about the space-time continuum and if you believe in multiple planes of existence, etc. Perhaps the girl continued to exist in the past where she had traveled to, but could not travel back to her own time, because she didn't exist in the future. That's why "Back to the Future" was so wacky ... when he made it less likely that his parents got together, his own existence begin to be threatened.

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? C'mon, are we still trying to multiply with 0? Two times 0 = what? Zero. So saying it will be twice as cold as 0 is pointless.

6. Answer truthfully (yes or no) to the following question: Will the next word you say be no? My response: "Truthfully? No." The trick here is not to assume you have to answer in 1 word. The "next word" I said wasn't no, and so my response was correct, technically.

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

Seriously, if you're in a car going the speed of light, you have far more things to worry about than the lights!

8. I conclude with this challenge:

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

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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?

I actually don't think either can exist. Basically, the bullet would have to be infinitely piercing and the armor would have to be infinitely resistant. However, by definition, infinity in unattainable.

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

This one depends which definition you use for drowning. The question would imply that the intended definition is to die from lack of oxygen due to submersion in water. In that case, the eternal life feature of the fountain should keep you alive. Extensive testing would need to be done to to determine the effects of trying to drown someone in this fountain. Alternately, we can simply claim that a fountain of eternal life does not exist and therefore it is not possible to drown in it.

3. Your mission is to not accept the mission. Do you accept? Doesn't matter, does it?

Accepting a mission does not mean you will succeed and accomplishing the goal of the mission does not require acceptance of the mission. So, it does not really matter how you answer. You can accept the mission, thereby failing it, or you decline the mission, thereby meeting the objective.

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 we must assume that time travel is possible, which I do not personally believe. Then, we need to understand how events occur in time. If there is only one time line and traveling through time equates to hoping to a different point on that line, then this paradox would cause a potential loop where every other iteration the girl was born, traveled back in time and killed her grandmother, thus creating an iteration where she does not exist to go back and kil her grandmother. Alternately, events could all occur in separate streams. So, the girl would skip over to a different time stream where her grandmother exists, kill her there and then there would be to girl born in that time stream. Then the girl could live out her life in the time stream where she killed her grandmother or she could return to her own time stream and take her grandmother out to diner.

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?

My interpretation of this would require a defined comfortable temperature, say 70F. A measure of how cold it is would be determined by how far below 70F the temperature fell. If the temperature today was 0f and tomorrow was expected to be twice as cold, then I would expect it to be -70F. Of course, there are some major flaws with this approach. Everyone would have their own comfortable temperature, so the statement would mean different things to different people. More than likely, the meteorologist who made the prediction would be basing this on their own comfortable temperature. Also, using my example, this would require a huge change in temperature.

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

I like the answer above using a different, less obvious answer. I would go with "probably not".

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

I have not gotten to the point in physics to really understand what would happen here. My intuition tells me that the light particles would be blasted out of the bulbs at roughly twice the speed of light, but would quickly decelerate to the normal speed of light. However, I have read a bit on the theories and it would seem that light does not play by the same rules.

8. I conclude with this challenge:

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

My answer to this is very similar to my answer to the first question. Infinity does not actually exist. So, God Almighty can not really be infinitely powerful and can not create a rock which is infinitely heavy.

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The speed of light is a constant. Light cannot ever travel at twice the speed of LIGHT. It's light! That's like asking what is the maximum amount a brick can weigh, and getting the response 'twice as much as a brick can' it makes no sense, and it doesn't answer the question!

All I want to say about this is very bad analogy. A brick will "weigh" differently depending on the amount of force used (gravity). In order to correct your statement, you would need to use the word "mass". Yes, it is a minor thing, but when we're talking physics, watch what words you use.

However I agree with the rest of the post you made Incognitum. Since c (speed of light) is a universal constant, there should be no visible light emitted from the light source, in this case the headlights. The only problem i could foresee with our explanation would be we are basing our observation off of Einstein's Special Theory of Relativity, which only corroborates with speeds up to the speed of light. So objects traveling the speed of light are not included.

Regardless, as mentioned previously, the situation is impossible.

So the short answer to #7? "You would probably think you're headlights are broken"

We also solved #4 using physics. In order for a time machine to be possible, you would need to accelerate faster than the speed of light in a vacuum, which is impossible in our current understandings. Therefore the scenario is impossible.

My non-technical answer for #4 would be "the time police would stop her before she could commit the offense, since they obviously would know the exact time of the murder."

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ok, for the one about the grandmother. The girl could of went back in time and killed her grandmother after the fact that her grandmother's child(the girl's parent) was born, which still makes her exist because her mom or dad already was born. Also it doesn't tell what date she went back in time to. For all we know, she could of went 2 minutes back in time and the girl would still be alive.

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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.

The scenario clearly states that the girl was never born. So, it is not unreasonable to conclude that they girl went back to a time before her mother was born. You can not get around the question be changing the scenario.

Also, I don't think it is fair to question the reality of time travel. Using physics to explain the headlight question is fair, but this exercise is intended to consider what might occur if time travel were possible. Negating a condition of the puzzle does not solve the puzzle. It would be kind of like answering one of the Honestant/Swindlecant puzzles by saying that no one always lies or always tells the truth.

Finally, I would not rely on the time cops. If time travel really is possible, it would be extremely difficult for any time cops to detect any paradox and even more difficult to prevent them.

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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?

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

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

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.

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?

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

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

8. I conclude with this challenge:

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

1. They can both exist, easily. It depends which one is made first. A bullet can be made that can pierce through anything.. that exists of course. Then bullet proof armor is invented that can now resist everything. Or the bullet can be invented second. Whatever. What they can pierce/deflect would be determined when they were made. The SEARS tower was the tallest building in the world. We called it that. Then someone else built a taller one.

2. well u could drown, then be reawakened by the fountain, right?

3. "the" could refer to a different mission... it will be a true paradox if they change "the mission" to "this mission"

4. well if every time u go back in time, it creates a parallel universe, ALL time paradoxes are solved. because ppl dont realize time traveling backwards creates millions of paradoxes similar to that, just at an atomic and subatomic level. creating a new "branching universe" every time u go backwards solves all that

5. twice as cold doesnt exist, u have to make it half as hot. which would be still 0. thats not really a paradox

7. i dont think anybody knows

8. thats not even a frikkin paradox... i dont get it.

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#8 is a paradox because if god could make a stone that he couldn't physicaly lift, then he wouldn't be almighty. And if he cant make a stone that he couldn't lift, then he obviously isn't almighty.

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#8 is a paradox because if god could make a stone that he couldn't physicaly lift, then he wouldn't be almighty. And if he cant make a stone that he couldn't lift, then he obviously isn't almighty.

I disagree with this statement. 'Almighty' as is used in this supposed paradox is the ability to do anything. By God not doing something that he is capable of doing does not limit his ability to do said thing. Put another way, in the context of the "paradox":

God can make a stone he is not capable of moving, he does not, that is why he is God.

Put in another context that is perhaps easier to digest.

God can not lie, for if he did, he would cease to be God.

I guess the "paradox" simply illustrates the priciple that there are consequences, even for God. As Newton states, "To every action force there is an equal, but opposite, reaction force". There is opposition in all things.

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The light you would see from the headlights would appear to you to be going the speed of light. Any observer will always measure the speed of light to be the same, no matter how fast they are moving. However, it is impossible for a car, or any material object, to reach the speed of light, so this doesn't make sense.

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The light you would see from the headlights would appear to you to be going the speed of light. Any observer will always measure the speed of light to be the same, no matter how fast they are moving

Gondorian: Thank you!

Cipher22: you capitulated too quickly.

Incognitum: It looks like you should read some books on relativity

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All I want to say about this is very bad analogy. A brick will "weigh" differently depending on the amount of force used (gravity). In order to correct your statement, you would need to use the word "mass". Yes, it is a minor thing, but when we're talking physics, watch what words you use.

However I agree with the rest of the post you made Incognitum. Since c (speed of light) is a universal constant, there should be no visible light emitted from the light source, in this case the headlight.

So the short answer to #7? "You would probably think you're headlights are broken"

We also solved #4 using physics. In order for a time machine to be possible, you would need to accelerate faster than the speed of light in a vacuum, which is impossible in our current understandings. Therefore the scenario is impossible.

First, this is wrong. The MAXIMUM weight of a brick is a constant, regardless of specific gravity, density of atmosphere, variabilities in brick manufacture etc... The MAXIMUM amount will be the one where all these variables are at the position on the spectrum which results in greatest measure of weight. This is what MAXIMUM means. Therefore, it is a perfect analogy to the speed of light, which also is a constant.

Second, no, this is wrong. You will not think your headlights are broken because relative to your position in the car your headlights will travel away from you at the speed of light. Celeritus ('C') is constant relative to ALL observers; including you in the car.

Third, Being as no time machine has ever been invented, how do you know the operating principle used in it's design? ...Unless you have a time machine and went to the future to ask...

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