29 Jun 07
I have a question. And I am very curious about it. I cannot answer it, maybe you all can. And this is not a riddle. This is a question in all seriousness.
If you were in a pitchblack room and there was one flying beetle inside this room with you (for instance, a junebug), and this beetle was currently flying aboout this room, (btw this room has no visible entrances or exits)
Would you be more likely to run into this beetle if you were moving or if you were not moving?
(The room is about 10 ft by 25 ft.)
29 Jun 07
Originally posted by EinsteinMindAs a result of global warming junebugs are now maybugs.
I have a question. And I am very curious about it. I cannot answer it, maybe you all can. And this is not a riddle. This is a question in all seriousness.
If you were in a pitchblack room and there was one flying beetle inside this room with you (for instance, a junebug), and this beetle was currently flying aboout this room, (btw this room has no vi ...[text shortened]... is beetle if you were moving or if you were not moving?
(The room is about 10 ft by 25 ft.)
Flat on the floor is my guess to be safe.
Can they smell blood?
29 Jun 07
1 edit
Originally posted by EinsteinMind
I have a question. And I am very curious about it. I cannot answer it, maybe you all can. And this is not a riddle. This is a question in all seriousness.
If you were in a pitchblack room and there was one flying beetle inside this room with you (for instance, a junebug), and this beetle was currently flying aboout this room, (btw this room has no vi ...[text shortened]... is beetle if you were moving or if you were not moving?
(The room is about 10 ft by 25 ft.)
29 Jun 07
Originally posted by EinsteinMindhow can I run into something while standing still???
I have a question. And I am very curious about it. I cannot answer it, maybe you all can. And this is not a riddle. This is a question in all seriousness.
If you were in a pitchblack room and there was one flying beetle inside this room with you (for instance, a junebug), and this beetle was currently flying aboout this room, (btw this room has no vi ...[text shortened]... is beetle if you were moving or if you were not moving?
(The room is about 10 ft by 25 ft.)
And,seriously, i think that while moving one is more prone to the crash.
30 Jun 07
If you are moving as well as the beetle then doesnt that mean the beetles mean velocity relative to you is increased? And intuitively a faster moving beetle must crash more times per hour than a slower moving one.
Hence your chances of a collision are increased if you move too.
Or have I missed something?
30 Jun 07
If the room is about 10 by 25, that means, assuming you take up around a square foot of space for simplicity, that if you stand still, there's a 1/250 chance the bug will hit you in any particular moment.
If you both move, you both have to occupy the same space at the same time, which would mean the chances are (1/250)² or 1/6250.
So provided you keep moving, you should be less likely to get hit.
I think. personal experience of me being locked in dark rooms with beetles would suggest otherwise.
30 Jun 07
Originally posted by wolfgang59No, it works if both motions can be considered random. Of course, there's probably a distribution of probabilities, but there's not enough info in the question for that.
That answer is only correct if
a) the beetle teleports to random areas of the room
and
b) the collision has to be in a particular square foot of the room
so it doesnt answer the question
Also, the answer assumes that to collide they have to be in the same square foot of the room (a fair assumption I feel), there's no preference in the calculation for any particular square foot.
30 Jun 07
Originally posted by agrysonHere's our resident physicist! Trust agryson's answer.
No, it works if both motions can be considered random. Of course, there's probably a distribution of probabilities, but there's not enough info in the question for that.
Also, the answer assumes that to collide they have to be in the [b]same square foot of the room (a fair assumption I feel), there's no preference in the calculation for any particular square foot.[/b]
30 Jun 07
1 edit
Originally posted by agrysonI believe it does reference to a specific Square foot (i think)
No, it works if both motions can be considered random. Of course, there's probably a distribution of probabilities, but there's not enough info in the question for that.
Also, the answer assumes that to collide they have to be in the [b]same square foot of the room (a fair assumption I feel), there's no preference in the calculation for any particular square foot.[/b]
in the given room there is (if completely random) a 1/250 chance of the junebug being in any given squre foot.
If the person moves in a completely random manner, there is an equal chance of them being in any given square foot.
The chance of both being in Square A is 1/250*1/250
Since there are 250 squares in the room, i believe it follows that the odds (in a completely random environment with teleportation etc.) are:
1/250*1/250*250 = 1/250
Please tell me where i am mistaken, which i probably am..
I would also like to say that if the bug can move at any speed, then you moving is identical as far as collisions is concerned to the bug moving twice as fast.
the chance of you colliding with the wall increases by quite a bit if you start moving though.
30 Jun 07
Originally posted by crsmithersI don't know why you multiply by 250 at the end there.
The chance of both being in Square A is 1/250*1/250
Since there are 250 squares in the room, i believe it follows that the odds (in a completely random environment with teleportation etc.) are:
1/250*1/250*250 = 1/250
If I am in the room and moving around randomly, the odds of me occupying any particular square at a particular moment is 1/250. if the bug is moving around as well, the odds are the same for it to occupy any particular square. For both the bug and myself to occupy the same square at the same moment is simply the multiple of these, i.e. 1/62500 (I think I missed a 0 in my previous post)
I too may be wrong, it's a while since I did probability, but I still don't know why you multiplied by 250.
Also, there's no need for teleportation, random movement is enough to satisfy the maths.
01 Jul 07
Originally posted by agrysonOk. Let me try to put this another way. IF they are moving at the same speed, then A will occupy a square on any given move. This square could be A1 or B2 or whatever. We assume that since he is in the room he must occupy one square. If the Bug moves to a square every move as well, and is completely ignorant as to the position of the person, then there is a 1/250 chance that he will be in the same square as the person.
I don't know why you multiply by 250 at the end there.
If I am in the room and moving around randomly, the odds of me occupying any particular square at a particular moment is 1/250. if the bug is moving around as well, the odds are the same for it to occupy any particular square. For both the bug and myself to occupy the same square at the same moment is s ...[text shortened]... .
Also, there's no need for teleportation, random movement is enough to satisfy the maths.
If you play the lottery, then changing your numbers every week doesn't decrease your chances of winning, for the same reason.