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A physics brain teaser!

  1. 0
    Wadey101mposted 7 years ago

    If today is zero degrees and tomorrow is going to be twice as cold, what temperature is tomorrow going to be?

    1. Mark Knowles profile image61
      Mark Knowlesposted 7 years ago in reply to this

      Twice as cold as what?

      1. 0
        Wadey101mposted 7 years ago in reply to this

        Twice as cold as Zero degrees

    2. BDazzler profile image82
      BDazzlerposted 7 years ago in reply to this

      Assume 100 degrees is twice as hot as 50 degrees
      Assume 25 degrees is half as hot as 50 degrees and is therefore 25 degrees is twice as cold as 50.
      Assume Zero C in question ...
      Covert to F temp now  =  32
      Half of 32 is 16
      Covert 16 F to C and we have -8.9 degrees C

      1. countrywomen profile image59
        countrywomenposted 7 years ago in reply to this

        BDazzler- You dazzle with your intelligence smile

        1. BDazzler profile image82
          BDazzlerposted 7 years ago in reply to this

          You are quite kind, and I don't think I congratulated you on your marriage!

          Congratultions!

          1. AEvans profile image71
            AEvansposted 7 years ago in reply to this

            Yes BDazzler Congrats again!!!!! hehehehe big_smile

      2. 0
        sandra rinckposted 7 years ago in reply to this

        Ah but C doesn't have a zero degree and neither does F, so even if you did convert the temperatures all have but skipped Zero assuming that zero degrees is hot or cold.  But I really like how you put this, I am just not sold yet. smile

        1. BDazzler profile image82
          BDazzlerposted 7 years ago in reply to this

          Weellll ... I have a degree in Science and Math with a secondary emprasis on Chemistry.  This is the first I've heard about neither celcius or farenhiet having a zero ... I think you may be mistaken on this one Sandy.  Celcius is defined as the scale between the freezing point of water and the boiling point of water ... being between zero and 100 inclusive.

          There is an error in this calculation, (well not an error, there's an implied assumption that is incorrect ) I'm just waiting for somone else to find it and point it out ... but the non-existance of zero isn't it.

          1. dipless profile image85
            diplessposted 7 years ago in reply to this

            One of the problems with this analysis of the problem is if you keep halving starting at 100 then you will never actually reach 0 i.e. 100 goes to 50 to 25 to 12.5 to 6.75 to 3.375 to etc all the way to infinity but you would still never reach 0 degrees so you can't use this method.

    3. packerpack profile image60
      packerpackposted 7 years ago in reply to this

      There is nothing called cold in the world of physics. We measure heat and not cold. Temperature in any scale gives us the indication of presence of amount of heat energy and not cold energy as there is nothing called cold energy. Cold in just the absence of heat. Since we cannot measure cold so the question itself becomes invalid!

    4. 0
      Béla Mongyiposted 7 years ago in reply to this

      Error: unspecified referential index

      How can your robotic brain come up with such a question?

  2. Misha profile image75
    Mishaposted 7 years ago

    As an ipod in a glass of juice lol

    1. 0
      Wadey101mposted 7 years ago in reply to this

      Lol, just realised that I still kept the title of the request I was answering. Hehe thanks for that, I've changed it now :-)

    2. nicomp profile image61
      nicompposted 7 years ago in reply to this

      Well done.

  3. Paraglider profile image88
    Paragliderposted 7 years ago

    Meaningless question. What scale are we using? Farenheit, Celsius or Kelvin?

    1. Mark Knowles profile image61
      Mark Knowlesposted 7 years ago in reply to this

      But - even if we use a scale, it doesn't mean anything. "Cold" is a relative term big_smile

    2. 0
      Wadey101mposted 7 years ago in reply to this

      Celsius my friend.

      1. Paraglider profile image88
        Paragliderposted 7 years ago in reply to this

        OK. Twice as cold can be taken to mean the same as half as hot, which is reasonable because temperature is a measure of hotness (not of heat which is measured in joules).

        So first convert to Kelvin, so that you are working on an absolute scale. Then divide by two (which works because the scale is linear) and convert back to Celsius if you want to.

        But temperatures of 136.5K (or -136.5C) are not survivable and so, subjectively are far colder than 'twice as cold'. In fact, though the temperature scale is linear, the human response to it is highly non-linear (rather like our response to loudness).

        1. BDazzler profile image82
          BDazzlerposted 7 years ago in reply to this

          Para's resposne is more correct than mine .... my response had one major problem ... a "Degree" in C is "Bigger" than a Degree in F and my response failed to take that into consideration.

          Since a Degree K is the same size as a Degree C, Para has come up with the right answer.

          1. 0
            sandra rinckposted 7 years ago in reply to this

            Well obviously I don't get it but in my mind, 0 and -0 are the same degree because this degree in terms of heat is undefined but hotter than whatever hot is, and likewise the same degree is absolute terms of cold is colder than whatever cold is.

            So in one lump sum you could say that the hotter it is, the colder it is.  In stupid Sandy terms, it's like putting your hand it really hot water, it friggin burns it stings, just the same as putting your hand in really cold water, it friggin burns and stings.  Now put your hand in water that is twice as hot as whatever really hot it and it's likey you wouldn't feel a thing, same with cold.

            Or dry ice is so cold it is hot or so hot it is cold.  Still not sold and and still view the the scales as irrelevant. 0x0=0 and -0x0=0 and -0x0=0 so -0[0] and 0[-0]  and 0/0=0 and -0/0=0 etc.. all = 0.

            so just by the word problem alone 2x0 still = 0. and -2x0 still = 0...

            but please keep trying to convince me.   

            smile

            1. Misha profile image75
              Mishaposted 7 years ago in reply to this

              I'm with you here My Goddess smile

              Never thought of changing the scale in the midst of calculations to be a valid method, and frankly really am surprised the guys seemed to take this idiotic challenge seriously smile

              1. 0
                sandra rinckposted 7 years ago in reply to this

                me too, I guess that is why it was called a physics brain teaser. smile  after all, I am not a physicist.    doh! big_smile

                1. BDazzler profile image82
                  BDazzlerposted 7 years ago in reply to this

                  Seriously? Of coruse not, that's why I posted my erroneous answer first.... tongue it's just that some of us find our fun differently than others: cool

                  Sandy your argument is valid for the Kelvin scale, in which zero truly is zero.  On the celsius scale, zero is defined as the freezing point of water.  So it's not absolute zero, it's jut an arbitrary number that someone called zero.

            2. Make  Money profile image72
              Make Moneyposted 7 years ago in reply to this

              Which direction is the wind blowing?  Just joking. smile

              I would have said 0 too.

              0x2=0

  4. knolyourself profile image61
    knolyourselfposted 7 years ago

    Actually there are a number of answers on Google. This has been one of them:
    "That would depend on what temperature scale you are using. The scale which places zero degrees at the absolutely coldest point is called Kelvin. It has the same degree divisions as Celsius does. "Absolute zero," or zero degrees Kelvin, is the coldest temperature possible. This is the temperature at which all molecules stop all movement.
    So, if you are measuring in Kelvin, twice as cold is not possible. (0/2=0) However, if you are using the Celsius scale, zero degrees is actually 273.15 degrees above absolute zero. So, twice as cold would be -136.575 degrees Celsius. Similarly, absolute zero in Fahrenheit is -459.67. Thus, from zero degrees F, twice as cold would be -229.835 degrees F."

    1. 0
      sandra rinckposted 7 years ago in reply to this

      Still the answer would be zero degrees.  But I think this information is wrong.  1 degree Celsius is 32 degrees Fahrenheit so neither scale address absolute zero temperature. 

      Kelvin represents absolute zero temperate, and temperature address "heat or energy", really it is neither hot or cold.  Like Mark said, cold is a relative term. 

      So it would still be the same 0[-0].

  5. greathub profile image80
    greathubposted 7 years ago

    It depends on relative humidity too.

    Moreover what is hot for you may be cold for me.


    e.g. 21 degree celsius is hot for canadians and the same temperature is cold for people living in warm climates.

  6. dipless profile image85
    diplessposted 7 years ago

    Temprature is a measure of energy in a system and you can use different equations and laws to calculate the temprature in a system depending upon what you are measuring. For example you could use the 2nd law of thermodynamics and relate the temprature to the entropy of the system. Or we could use the zeroth law of thermodynamics, but the we need an idealized situation. The problem is that this question is too openended and therefore not a valid question, hence the problems in answering so there really is no VALID answer.

  7. dipless profile image85
    diplessposted 7 years ago

    Error: unspecified referential index

    How can your robotic brain come up with such a question?

    LOL big_smile

  8. Patty Inglish, MS profile image89
    Patty Inglish, MSposted 7 years ago

    Among other things, it's a question sometimes asked in employment interviews to examine problem-solving skills -- Does the candidate 1) choose a scale and explain why (s)he chose it and offer an answer, 2) give an explantion that there is no reference point, or 3) give up and say "I dunno"? -- Or does he/she do something else, like call the Physics Dept of the local University from the HR guy's phone and relay the answer?

    And, these questions can frustrate job candidates, espeically in a recession or after a layoff when a person may be worried about how to feed his/her children.

  9. ocbill profile image76
    ocbillposted 7 years ago

    Uh yeah, like I will believe the TV weather forecaster. LOL.
    Although, I like the -8.9 C answer though Alex Trebek

  10. Hawkesdream profile image78
    Hawkesdreamposted 7 years ago

    Who cares anyway, any temperature that is at 0 or below is gonna be bloody cold. Get out your woolley jumpers, hat gloves and scarfs and furry boots. Your temperature will be comfortable enough.

  11. B.Z. Alixandre profile image77
    B.Z. Alixandreposted 7 years ago

    My problem with the question is along the lines already stated that cold is not a "real" science term.  If you conclude that temperature is a measure of energy in regards to how fast particles are moving then my answer would relate to half as cold being the point in which the molecules are moving half as fast.  But the progressions of speed in particles is not linear and not equal to other particles.  Ie: for water approaching 100 C (but not yet arrived at) it takes more energy to obtain 100 C because it becomes steam at 100 C.  Imagine your pot of boiling water.  The part hovering over the pot as steam is 100 C but the part in the water is 99.9 C (or close to)  It takes time at the point of transformation from one state or another.  Alcohol has a much lower boiling and freezing point, therefor the particles are moving at different speeds as water at the same temperature.  Therefor half as cold as 0 C will be different for alcohol than for water.

 
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