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Can anybody solve this simple and interesting mechanics problem ......

  1. Sexy jonty profile image60
    Sexy jontyposted 7 years ago

    Problem : A bird falls from a tree of 20m height. It reaches to ground in 2sec. A bear sees it from a distance of 40m and run to catch it, reaches in 4sec. What is the visible color of the bear?
    Give your answer along with the reason ......

    1. sannyasinman profile image60
      sannyasinmanposted 7 years ago in reply to this

      Red with anger. He was too late and the bird flew away.

    2. ediggity profile image60
      ediggityposted 7 years ago in reply to this

      The bear is white, because the acceleration due to gravity is closest to 10 m/s^2 at the North Pole.

      1. Sexy jonty profile image60
        Sexy jontyposted 7 years ago in reply to this

        BOOOOOOOOM ........

        BANG ON THE TARGET ........

        ediggity ......

        You are the only person who cracked it ....

        Very intelligent I must say .....
        Kindly everyone at the forum ....
        ediggity is right to the answer and those who not understood it .... can post ..... I will help them to explain ....

        1. profile image0
          Scott.Lifeposted 7 years ago in reply to this

          Except there are no trees at the north pole, or birds for that matter, I'm speaking as someone who studies biology, not physics.

          1. Sexy jonty profile image60
            Sexy jontyposted 7 years ago in reply to this

            Very well said Scott .....

    3. Sexy jonty profile image60
      Sexy jontyposted 7 years ago in reply to this
    4. profile image59
      bobcat_robposted 7 years ago in reply to this

      No body saw it, because the bear is the one who who saw the falling  bird. another answer, is if the bear is in north pole, maybe its white. if it is in the jungle, maybe brown






  2. retellect profile image79
    retellectposted 7 years ago

    Brown? I dunno? Can't figure it out! Is there something I'm missing? :s

  3. jenblacksheep profile image83
    jenblacksheepposted 7 years ago

    No bear could run that fast!

  4. Sexy jonty profile image60
    Sexy jontyposted 7 years ago

    Wow men ....... I thought I would be answered in few minutes with that simple question .....
    But it took more than two replies .... and 50 minutes ......

  5. Sexy jonty profile image60
    Sexy jontyposted 7 years ago

    Somebody answer it ..... it's now almost two hours for the answer to come .....

  6. Lee Boolean profile image60
    Lee Booleanposted 7 years ago

    brown, no trees where the Polar bears are

    1. Sexy jonty profile image60
      Sexy jontyposted 7 years ago in reply to this

      Sorry lee boolean ..... it's not the correct answer .......

      1. Lee Boolean profile image60
        Lee Booleanposted 7 years ago in reply to this

        still puzzled how the bear could run at 10m/second... maybe he has a Lam-bear-ghini

        1. Sexy jonty profile image60
          Sexy jontyposted 7 years ago in reply to this

          Lee Boolean just don't go to the reality part .......
          Ok let assume :
          A bird falls from a tree of 20m height. It reaches to ground in 2sec. A bear sees it from a distance of 10m and run to catch it, reaches in 4sec. What is the visible color of the bear?
          Give your answer along with the reason ......

          Now it's ok ....

          1. Lee Boolean profile image60
            Lee Booleanposted 7 years ago in reply to this

            sorry SexyJ, I am stumped...

            1. Sexy jonty profile image60
              Sexy jontyposted 7 years ago in reply to this

              Hey Lee Boolean ...... don't give up ..... answer some part is in the question ..... just read it carefully ...... I have given big hint in my previous post ......

    2. Lee Boolean profile image60
      Lee Booleanposted 7 years ago in reply to this

      hmm, was wondering about this mechanical problem on my way home, I must say I am a little disappointed at the answer, maybe its one of those "insider" jokes that only makes sense when you assume a degree in physics. I for one would never have even thought about the speed of the bird falling, but then I did have the same argument as Scott regarding trees on the north pole, but I guess the velocity of the bird is a much clearer give away.

      Anyhow... here's a quick riddle for you (not nearly as complicated):... why do polar bears eat seals and fish but never penguins?

      1. profile image0
        Scott.Lifeposted 7 years ago in reply to this

        Because there are no penguins in the North Pole only the southern arctic

  7. zadrobi profile image60
    zadrobiposted 7 years ago

    This isn't a mechanics problem-- this, if anything, is a velocity question superimposed by ambiguity.

    1. Sexy jonty profile image60
      Sexy jontyposted 7 years ago in reply to this

      Think brother ...... just think .......
      This question now I am telling you was asked in IIT exams .....
      just think more and reply .......

  8. Helen Cater profile image61
    Helen Caterposted 7 years ago

    A bear does not change color so it would be the same as when it set off. Was it a polar bear, black bear, or brown bear? Did the bird fly away as the bear would have been 2secs too late. Did the bird die? Did the bear eat it? Maybe the polar bear would look a little red around the mouth. I hate these riddles.

    1. Lee Boolean profile image60
      Lee Booleanposted 7 years ago in reply to this

      you mean you cant -bear- these riddles?

      1. Helen Cater profile image61
        Helen Caterposted 7 years ago in reply to this

        It's grizzly!!

        1. Lee Boolean profile image60
          Lee Booleanposted 7 years ago in reply to this

          polar-izing to say the least...

  9. flighty02 profile image80
    flighty02posted 7 years ago

    Well now, assuming that the bird was dead before the bear got there (2 seconds too late) the bear wouldn't have a visible color to the bird.

  10. Sexy jonty profile image60
    Sexy jontyposted 7 years ago

    sannyasinman :  Well tried men ...... but wrong .......

    Helen Cater : Don't know the answer ...... It's fine ...... but don't say it a riddle ..... The topic says "MECHANICS PROBLEM" ......
    So there may be a valid answer to it ...... Not a riddle answer .....



    flighty02 : A real bad answer to a simple mechanics problem .....

    Lee Boolean : I think you have quit it way before ......

  11. Helen Cater profile image61
    Helen Caterposted 7 years ago

    I guess we better all stay away from this thread as we are dumbos.

    1. Sexy jonty profile image60
      Sexy jontyposted 7 years ago in reply to this

      Now who says that ........ I am not saying anyone dumb .... but I am just saying your attempt to reason is wrong that's it ....

      Helen Cater your hubs and fan club shows that you are far more creative than me ......

      This forum is just for the fun .......... So let's enjoy ......

      Sorry for previous post ........

  12. Paradise7 profile image84
    Paradise7posted 7 years ago

    The bear can't run that fast, so it's a moot question.  I think that's the right answer, or the sought-after answer, looking back at the other posts.

    It seems silly, though, like one of those papers with 90 instructions listed, and the first instruction is "read all the instructions before you begin", then it goes, take five, add two hundred, next instruction:  divide by five, next instruction:  multiply by seven...until you get to the last instruction, which says, "disregard all the instructions except for #1."

    1. Sexy jonty profile image60
      Sexy jontyposted 7 years ago in reply to this

      paradise7 ..... you're mistaken by whole of the problem ...

      It's a mechanics question ..... so what's in the question if I say car runs at 200km/sec .....

      on earth there is no such car ..... but if I put it in a question .... just by few calculations you would arrive to a answer which is practically not possible .... but on the paper and question it's the right answer .....

      1. Paradise7 profile image84
        Paradise7posted 7 years ago in reply to this

        The bear is white.  Is it?

        1. Sexy jonty profile image60
          Sexy jontyposted 7 years ago in reply to this

          And the reason .......

          1. Paradise7 profile image84
            Paradise7posted 7 years ago in reply to this

            Ah, I got it.

            Don't want to spoil the thread for other people.  It only LOOKS white...

            1. Sexy jonty profile image60
              Sexy jontyposted 7 years ago in reply to this

              please I said two colors ...... Ok white ...... give the reason ... and spoil the thread .....

            2. profile image0
              Madame Xposted 7 years ago in reply to this

              Come on Paradise - spill it smile

              1. Sexy jonty profile image60
                Sexy jontyposted 7 years ago in reply to this

                He don't know the reason .... he's just guessing ....

                HINT 2 :  Apply newton's equations of motion ......

                And you're to the answer ....

  13. Helen Cater profile image61
    Helen Caterposted 7 years ago

    I'm just going to sit and wait for the answer as I said I am useless at this and no offense taken. I just want to know the answer.

    1. Sexy jonty profile image60
      Sexy jontyposted 7 years ago in reply to this

      HINT : There are two answers(colors) ..... One visible color and one actual color  ....

      Think .......

  14. profile image0
    Madame Xposted 7 years ago

    The bear is the same color as the tree trunk and when he saw the bird fall he had to climb down 10m, which took him 4 seconds. However, the bird hadn't hit the ground before the bear started climbing down so the time of the bird falling and the bear climbing down were overlapped.

    1. Sexy jonty profile image60
      Sexy jontyposted 7 years ago in reply to this

      Madame X ..... not read the question properly .... Bear is not over the tree .... He is at distance from the tree .....

      1. profile image0
        Madame Xposted 7 years ago in reply to this

        The OP states that the bear saw it "from a distance". It didn't say whether that distance was horizontal or vertical.

        Ok let assume :
        A bird falls from a tree of 20m height. It reaches to ground in 2sec. A bear sees it from a distance of 10m and run to catch it, reaches in 4sec. What is the visible color of the bear?
        Give your answer along with the reason ......

        But I guess I'm still not right . . .

        1. Sexy jonty profile image60
          Sexy jontyposted 7 years ago in reply to this

          Madame X ..... It's the horizontal distance .....

  15. profile image60
    HealthTipposted 7 years ago

    "What is the visible color of the bear?"


    Could you possibly mean black and white as a bear sees things in black and white ?

  16. profile image0
    Madame Xposted 7 years ago

    Is the bear "white" becasue he's streaking so fast through the woods to get the bird?

    1. Sexy jonty profile image60
      Sexy jontyposted 7 years ago in reply to this

      No ..... Madame X it's mechanics ........

  17. habee profile image91
    habeeposted 7 years ago

    We give!

  18. zadrobi profile image60
    zadrobiposted 7 years ago

    The bear is black and white because it's a Panda Bear hehehe

  19. Paradise7 profile image84
    Paradise7posted 7 years ago

    The underlying physical premise is faulty, anyway.

    At least, I think it is.  I may have the wrong reason.  I want sexy to spill it. That way I won't look like such an idiot.

    1. profile image0
      Madame Xposted 7 years ago in reply to this

      There's no crime in looking like an idiot - I do it all the time . . . smile

  20. profile image0
    poetlorraineposted 7 years ago

    he did not catch it...... it fell to the ground

  21. profile image0
    Scott.Lifeposted 7 years ago

    1035 Hubs in Nine Months, now there's a math problem I can't figure out. WOW, you must live on Hubpages.

  22. Sexy jonty profile image60
    Sexy jontyposted 7 years ago

    Wow .... my simple problem is not yet answered ......

    It's now 14 hours and 45 replies ago when I asked .....

    1. Paradise7 profile image84
      Paradise7posted 7 years ago in reply to this

      Don't be cruel.  Everyone gave up.  Tell.  Please?

  23. zadrobi profile image60
    zadrobiposted 7 years ago

    I think he is just messing with everyone. Right now he's probably changing pants because he was laughing so hard.

    1. Paradise7 profile image84
      Paradise7posted 7 years ago in reply to this

      I thought I had it once, but then I saw a huge gaping flaw in THAT theory.  Maybe you're right, it's a piece of silliness and sexy is laughing up the sleeve right now.

  24. Sexy jonty profile image60
    Sexy jontyposted 7 years ago

    Ok .... For the people who are unable to figure it out ....... here goes my other hint .....

    HINT 3 : Use the formula .....

    S=ut + 1/2 a(t)2 ......

    the 2 in the red states that it is (t) square......

    Reading of formula goes like this ....

    S is equal to (ut) plus half a*(t) square .....

  25. Sexy jonty profile image60
    Sexy jontyposted 7 years ago

    It can also be read as ....

    S = ut + 1/2 a* t^2 ......

    1. Andres Canales profile image61
      Andres Canalesposted 4 years ago in reply to this

      The same color the bear always was. Remember, every formula works only within a range, and nothing at 4m/s will change of color, try it.

  26. Paradise7 profile image84
    Paradise7posted 7 years ago

    I was way out in the hinterland.  I had that thought of acceleration due to gravity but connected it in a different way to the bear.  I still had the answer "white", but not any where near a justifiable reason.

    Thanks for spilling the beans.  It was getting to me.

    1. ediggity profile image60
      ediggityposted 7 years ago in reply to this

      Well you thought of acceleration due to gravity, that's basically the answer, and you got the right color.  You get full credit from me.  I didn't bother reading through the posts.  I just answered the question, so I will go back and read your answers.  Good Job!

      1. Sexy jonty profile image60
        Sexy jontyposted 7 years ago in reply to this

        Eddggity now part for the other color ..... The actual one ....

        1. ediggity profile image60
          ediggityposted 7 years ago in reply to this

          I'm color blind.  I only see in black or white.  The visible spectrum of light varies at the Poles, and at the North there is total brightness.  In the summer the bear would be yellowish, because of oxidation, or greenish due to algal growth.  Black is the skin color, and it could reflect white.

  27. ediggity profile image60
    ediggityposted 7 years ago

    Thanks, but it only helps if you have/had a physics background.  Otherwise, most people would think about it philosophically, and not no where to start.

    1. Sexy jonty profile image60
      Sexy jontyposted 7 years ago in reply to this

      That's right ediggity .....
      I have a good physics background ....
      But forum answer are just like what you say (philosophical).......

      That's it wait for my other question ....

      1. ediggity profile image60
        ediggityposted 7 years ago in reply to this

        I love how I just answered a physics problem, and then misspelled the word know.

  28. Misha profile image74
    Mishaposted 7 years ago

    Umm, so the difference between 9.78 m/s2 on equator and 9.82 m/s2 on any pole is enough for that? Frankly does not make much sense to me. This difference is way less than the one between 10.0 and 9.82... If this is really the answer, i would say quite silly quiz...

    1. ediggity profile image60
      ediggityposted 7 years ago in reply to this

      It's a generalization, but yes the difference in gravity would affect the maximum velocity enough to make a difference.

      1. Misha profile image74
        Mishaposted 7 years ago in reply to this

        Seriously? Just a hint - for that to make anything close to sense, this bird had to fall from 19.64m. Maximum 19.67m. Now figure out why smile

        Oh, and there are no trees of that height where polar bears live, that's another hint from Scott to question idiocy. If you make a distinction between polar bear and grizzly, you have to take their habitat into account, too. smile

        1. ediggity profile image60
          ediggityposted 7 years ago in reply to this

          Like I said, it's a generalization (not exact), and yes it does make a difference.  Look at how to launch a space shuttle.  I already addressed Scott's post to Flightkeeper, and there was nothing wrong with what he said.  I don't need to "figure it out"  Here's a hint, I already did.

          1. Misha profile image74
            Mishaposted 7 years ago in reply to this

            You obviously never been even close to people who launch shuttles. lol Educate yourself about the theory of errors, it really can open your eyes. wink

            1. ediggity profile image60
              ediggityposted 7 years ago in reply to this

              Yep, you're right.  I'll try to educate myself more, so one day I can become close to the space shuttle launchers.

  29. Sexy jonty profile image60
    Sexy jontyposted 7 years ago

    The other actual color is .... black .....

    White is beacause the polar bear fur reflects sunlight .......

    1. ediggity profile image60
      ediggityposted 7 years ago in reply to this

      Now you answer this:

      http://lh3.ggpht.com/_3R6y9Z5zznI/SuTqzc11LgI/AAAAAAAAAB8/mz4ZPM4d5AQ/lim.jpg

      1. Sexy jonty profile image60
        Sexy jontyposted 7 years ago in reply to this

        where that limits tends to ..... is it 0 or infinity or it looks like a shape of earth in your question ......

        1. ediggity profile image60
          ediggityposted 7 years ago in reply to this

          It's the earth.

          1. Sexy jonty profile image60
            Sexy jontyposted 7 years ago in reply to this

            Wrong question ...... where is the function ......

            1. ediggity profile image60
              ediggityposted 7 years ago in reply to this

              The function is everything and Alpha and Omega is what goes into it.

              1. Sexy jonty profile image60
                Sexy jontyposted 7 years ago in reply to this

                kindly ... check it again it's again wrong queation .....

                1. ediggity profile image60
                  ediggityposted 7 years ago in reply to this

                  Just write out what it says, and you have the answer.

      2. Sexy jonty profile image60
        Sexy jontyposted 7 years ago in reply to this

        Hey .... I thought you want the proof .... L.H.S = R.H.S ....
        Is this a question or it's the fact you are telling to the world .....

        1. ediggity profile image60
          ediggityposted 7 years ago in reply to this

          No proof, I just wanted you to answer.  The proof is right there in front of you.

          1. Sexy jonty profile image60
            Sexy jontyposted 7 years ago in reply to this

            your question says if limit x--> 0 so f(x) would be infinity .... That's wrong question ....

            1. ediggity profile image60
              ediggityposted 7 years ago in reply to this

              It says as Alpha and Omega approach the world.

              1. Sexy jonty profile image60
                Sexy jontyposted 7 years ago in reply to this

                I got it .... are you talking about the alpha from universe that approaches to earth would destroy it .....

                1. ediggity profile image60
                  ediggityposted 7 years ago in reply to this

                  You're thinking in the right direction.  You forgot the Omega.  The Alpha and the Omega.

  30. Flightkeeper profile image77
    Flightkeeperposted 7 years ago

    I'm sorry this was stupid.  I thought it was a riddle and not a physics question.

    1. ediggity profile image60
      ediggityposted 7 years ago in reply to this

      What a debbie downer.  What was your riddle answer?  Like Scott said there are no trees in the North Pole, so you might be right also if you justify.

      1. Flightkeeper profile image77
        Flightkeeperposted 7 years ago in reply to this

        Yes, I'm a debbie downer. I still think it was dumb.

        1. ediggity profile image60
          ediggityposted 7 years ago in reply to this

          You still didn't give your riddle answer.  What were you thinking it was?

  31. Flightkeeper profile image77
    Flightkeeperposted 7 years ago

    My riddle answer was grey.

    1. ediggity profile image60
      ediggityposted 7 years ago in reply to this

      "Give your answer along with a reason"

      Jointy's rules not mine.

  32. Sexy jonty profile image60
    Sexy jontyposted 7 years ago

    Is that something to deal with christianity or greek alphabet .....

    1. ediggity profile image60
      ediggityposted 7 years ago in reply to this

      Christianity.

      1. Sexy jonty profile image60
        Sexy jontyposted 7 years ago in reply to this

        Does it relates to Jesus saying I am the alpha and Omega ....

        or it relates to tipler's theory .....
        or it relates to omega point .......

        1. Sexy jonty profile image60
          Sexy jontyposted 7 years ago in reply to this

          Hey ediggity where are you ..... reply .....

          1. Sexy jonty profile image60
            Sexy jontyposted 7 years ago in reply to this

            Ediggity when you arrive we would continue .... but for now I am thinking for a new good question ......

            1. Sexy jonty profile image60
              Sexy jontyposted 7 years ago in reply to this

              or it relates to collision to two bodies and shape appears to be of infinity symbol ......

              1. Lee Boolean profile image60
                Lee Booleanposted 7 years ago in reply to this

                that sounds like something from the kamasutra big_smile

                1. Sexy jonty profile image60
                  Sexy jontyposted 7 years ago in reply to this

                  It's collision of two spheres dude not the kamasutra .....

                  1. Lee Boolean profile image60
                    Lee Booleanposted 7 years ago in reply to this

                    pity really, smile sounds like much more fun for two bodies to keep at it for eternity

        2. ediggity profile image60
          ediggityposted 7 years ago in reply to this

          Yes, exactly, it relates GOD and to revelations the beginning and the end.

          I thought Tipler's theory was Omega Point?

          1. Sexy jonty profile image60
            Sexy jontyposted 7 years ago in reply to this

            So ediggity ..... It looks to me the question says when the beginning and end approach to earth ...... Their functionality together would be infinite ........

            1. ediggity profile image60
              ediggityposted 7 years ago in reply to this

              Yes exactly.  Good Job!

  33. Sufidreamer profile image83
    Sufidreamerposted 7 years ago

    lol - Not going to give the answer and spoil your fun, Lee - it might trap a few people, though smile

  34. Sufidreamer profile image83
    Sufidreamerposted 7 years ago

    You spoilsport, Scott!

    I reckon that you should provide us with a riddle, now big_smile

    Preferably one that is not a physics 'in' joke.

    1. Lee Boolean profile image60
      Lee Booleanposted 7 years ago in reply to this

      I agree with Sufidreamer, Scott you're it!

  35. profile image59
    bobcat_robposted 7 years ago

    Ok here is a simple riddle. If  very big basket is being filled up with candies and it takes 1 hour to fill it up. Rate of filling is that, the number of candies inside the basket doubles every minute. how long it will take for the basket to be quarter full?

    1. Lee Boolean profile image60
      Lee Booleanposted 7 years ago in reply to this

      I think I have this one... 58 minutes since the basket is full in 1 hour, and the quantity is doubled every minute, i.e. 60= full, 59= half full, 58 = quarter full....

      did I win anything?

  36. profile image59
    bobcat_robposted 7 years ago

    Ok here is a simple riddle. If  very big basket is being filled up with candies and it takes 1 hour

  37. profile image0
    R.G. San Ramonposted 7 years ago

    Oops. I can't believe I missed this thread. I hope I'm not too late. Just want to share an answer (without the math).

    When I looked at the post, the first thing that came to my mind was "green." Yes. Not that I'm green, but that if there was a tree, and a bird fell from a tree (perhaps a young one, trying to fly from its nest), and that a tree with a nest is absurd without its leaves, then the bear, even if painted blue by its owner ('cause a bear wouldn't run that fast without a trainer), will look green if you're looking from above ('cause the bear would have run for you instead if you're on land).

    Does this count? Or am I imagining too much? Or assuming too much?

    1. ediggity profile image60
      ediggityposted 7 years ago in reply to this

      The answer was focused toward physics and not philosophy, but all answers count.

      The bird in the tree falling was used to calculate the gravity of the place where the bear and bird were.  When you calculate the gravity it is closer to 10 m/s^2, which is at the North Pole.  A bear at the North Pole would be white.  The numbers used were nice and easy, so one could do the calculations easy.  The actual gravity at the North Pole is not 10 m/s^2, but closer to that than anywhere else.

      y=20m
      t=2s

      x=40m
      t=4s


      V^2=Vo^2 + 2(a)(y)


      x/t=Vx

      y=V-Vo/2 * (t)

      V=0 because the bird hit the ground

      1. profile image0
        R.G. San Ramonposted 7 years ago in reply to this

        Yeah I know, eddigity; I read through the entire thread. Just wanted to share a different perspective. smile But thanks for taking the time to respond.

  38. Mikewerk profile image60
    Mikewerkposted 7 years ago

    My guess is the bear would appear as a gray streak because the eye can only receive so much visual information at one time. Brown being a blended color and not a primary color might also attribute to the color distortion. If the bear were Red, Blue or Yellow, the eye would have less information to process and therefore see it in its natural color.

  39. profile image0
    zampanoposted 7 years ago

    sexy joint :
    does it bear a big pair of tits ?

  40. Nick B profile image83
    Nick Bposted 7 years ago

    Who cares?

    The fact that the bear is running at 36 kph would mean that I for one would have got the hell out of there pronto.

  41. profile image60
    garrukastrukposted 7 years ago

    i cant remember pass word.
    anyway, if the bird can fall vertically twice as fast as the bear can run horozontally that could be called in a mecanical term as a two to one compound ratio. but that is only part of that type of posible mech. nominclacture. somewhere it must be associated with an accual "visible" color posibly ryming with a mech. formula? am i warm\cold?

  42. darktriangle profile image60
    darktriangleposted 7 years ago

    From who's viewpoint????????????????????????????????????

  43. profile image0
    Will Bensonposted 7 years ago

    If the bird falls to the ground in 2 seconds, it couldn't have been at the top of the tree - so it didn't fall very far.

    Polar bears see well but don't live where trees do. Not white.

    Brown bears live where trees are but are considered to have the poorest bear eyesight (although this is challenged by some). Not brown.

    Black bears see well enough to spot a falling bird at 40m and live where there are trees.

    My ans is "Black."

  44. profile image0
    zampanoposted 4 years ago

    The bird fell from 19.6m high.
    The colour is Black.
    And it was not a bear.
    It was Usain Bolt. haha !

 
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