Monday, January 14, 2013

Situation 1 (Discussion Closed)

John did the following experiment.

He dipped his hand into a beaker of ice water for a minute before dipping it into another beaker of water at room temperature. He then commented that his hand in the beaker with the water at room temperature felt very warm and comfortable.

Peter who happened to be around then dipped his hand into the same beaker of water at room temperature. However, he claimed that his hand felt cold.

Can you explain the difference in their experiences?

Please give your comments using the "comment" function.
You will need to:
1) provide at least one comment of your own and
2) provide comments on at least another two of your friends' comments.

All comments are to be meaningful and serve to build more knowledge among your peers and yourself. Have Fun!

Mr Ang

Explanation:

As the temperature of John's hand was higher than the ice water, his hand lost heat to it. Hence, his hand would feel cold.  His hand would then be of a lower temperature as compared to the water in the other beaker at the room temperature. His hand therefore gained heat. This explains why he felt warm.

Peter, on the other hand, felt cold as he lost heat to the water at the room temperature. The temperature of his hand is probably higher than the room temperature.

Scientific Principle:
Heat travels from a hotter object to a colder object until both have the same temperature.

Common misconception:
  • gains coldness (wrong) should be lost heat
This discussion is officially closed.

79 comments:

  1. Dear class,

    This will be the format expected of you when posting a comment. It should indicate who you are speaking to, either to the class or some individuals. You will also have to sign off your name at the end of your comment.

    Mr Ang

    ReplyDelete
    Replies
    1. Dear Darren,

      I think your answer is correct but you have to shorten it as during exam,you cannot write that long an answer.


      Delete
    2. Opps Sorry, I posted it in the wrong colum.

      Delete
  2. Dear class,

    I sincerely hope that this demonstration in class helps you in your learning journey with this blog.

    Mr Ang

    ReplyDelete
  3. Dear friends,

    I have found the answer.It is because before John dipped into the room temperature water,he transferred some cold water into the room temperature water and the water gain heat from the room temperature water.

    Zheng Heng

    ReplyDelete
    Replies
    1. To Zheng Heng,

      I think your answer is wrong. This is because Peter have dipped his hand into some warm water and his hand felt cold in the room temp water.

      Sincerely,
      Sakinah

      Delete
    2. dear Zheng heng

      I think your answer is correct.

      Delete
  4. Dear class,

    One of them felt cold and the other felt warm. This may have happened as the room temperature changes at different times.Or it may have happened as Peter's hand may have been colder than John's hand.

    Chinmaya

    ReplyDelete
    Replies
    1. From Chin Yin Shuen
      Dear Chinmaya, I think you are correct!





      [Check out my answer.Mine is about the same as yours.]

      Delete
  5. Dear Mr Ang,

    Thank you Mr Ang,I appreciate your work.




    Zheng Heng

    ReplyDelete
  6. Dear class,
    It was because when John dipped his hand into the cold water, the temperature of his hand dropped as heat transferred from his hand to the cold water. So when he dipped his cold hand into the room temperature water, he felt warm because the temperature of his hand rose as he had transferred the coldness to the water.

    When Peter dipped his hand into the same beaker of water, the temperature of his hand is at normal temperature but the water is cold now. He felt cold because the temperature of his hand is warmer than the water temperature and he has transferred heat to the water.



    From: Darren Lim.

    ReplyDelete
    Replies
    1. Mothiki Eswara AnirudhJanuary 16, 2013 at 3:46 AM

      dear Darren
      I think your answer is correct.

      from Anirudh

      Delete
    2. Dear Darren

      I think you r corret can u tell me where u got your answer or did u think about it.....?

      Delete
    3. Dear Darren,

      I think you is right.

      Delete
  7. To all of you who have posted your views on situation 1, I would like to thank you for your pro-activeness. Well done!

    Here are some points for us to ponder...
    1) What exactly is heat and what is coldness?
    2) What can be transferred and what cannot be transferred?
    3) What do we mean by "transferred" in this situation?
    4) Are there certain terms ( verbs and prepositions) we can use to explain the situation with respect to the topic "Heat"?

    Cheers...Mr Ang

    I suggest that some of you might want to read up a little from the textbooks or Internet.

    ReplyDelete
  8. Dear Darren,
    I agree with your answer.





    Sze Jing

    ReplyDelete
  9. Dear friends,

    John felt warm because heat energy travels from hotter place to colder place.



    from:Sze Ni

    ReplyDelete
    Replies
    1. Dear Sze Ni I think you are right as we learnt on 22 of January 2013

      Delete
  10. Dear Darren,

    I agree with you.



    From:Sze Ni

    ReplyDelete
  11. Dear friends,

    I think Peter puts its hand into the ice water and wait for a while then put inside the water. (tempreture room)

    ReplyDelete
    Replies
    1. Dear Sze Jing,

      I think you are right.

      Delete
    2. Dear Sze Jing and Sze Ni,

      I think you are right

      From:Pashea

      Delete
  12. Dear Darren and Zheng Heng,

    I think your answers are correct

    ReplyDelete
  13. Dear classmates,

    My answer is:
    Heat is a form of energy that flows from a hotter object to a colder object until both reach the same temperature. Therfore when John puts his hand in the cold water and then into the room temperature water,he felt warm.But Peter only dips his hand in the room temperature water,so he felt cold.


    Wu Rui

    ReplyDelete
    Replies
    1. dear wu rui
      I think your answers are correct
      darren

      Delete
  14. Mothiki Eswara AnirudhJanuary 16, 2013 at 5:17 AM

    Dear Class,
    To answer the first question of Mr.Ang
    1. Hear is a form of energy which can be natural or manmade. Example for natural source is Sun, gloworm etc. Man made sources of heat are Fire, lighted bulb etc.
    Coldness : I think it is absence of Heat and hence we feel cool.

    ReplyDelete
    Replies
    1. Mothiki Eswara AnirudhJanuary 16, 2013 at 5:19 AM

      Typo error: Please note for Heat I typed as Hear in the above line. So read as 'Heat'

      Delete
    2. I think you r corret.

      Delete
    3. Dear Anirudh,
      I think you are right too!





      Sze Jing

      Delete
  15. Dear Wu Rui,

    Could you elaborate more on what actually happen when John placed his hand into the two beakers? 

    ReplyDelete
  16. Dear Friends,

    I found the website that might help for Question 1. Here is the website : http://science-is-easy.blogspot.sg/2009/10/what-exactly-is-heat.html

    Hope it helps....

    ReplyDelete
  17. Chin Yin Shuen

    Dear friends,I think Wu rui's answer is correct.Peter's hand might be a little cold before he put his hand into the warm water.

    And about what Sze Jing replied...I find it half-correct. This is because the question didn't say anything about Peter putting his hand into the icy water.

    ReplyDelete
  18. Dear Stacey,

    Thanks alot for th website!^_^




    Sze Jing

    ReplyDelete
  19. Dear friends

    you can find out more in this website:http://www.letstalkscience.ca/programs-and-services/hands-on-activities/physics/is-feeling-always-believing.html
    It tells you why . I hope it helps more>_<
    Sze Jing

    ReplyDelete
    Replies
    1. Oh thanks i will find more about it

      Delete
    2. Thanks it helped a lot ^_^

      Delete
  20. Dear friends,

    Here is a website I found from the internet: http://academic.uofs.edu/faculty/cannon/kidsjudge/kj04/celiia2.html
    Hope it helps ^_^

    From:Sze Ni

    ReplyDelete
    Replies
    1. It helps i heard that the website she goes was the website that u post


      Thanks

      Delete
    2. sry i mean the website that stacey went

      Delete
    3. Thank you Sze Ni it really helps a lot and I also think its right . ^_^

      Delete
    4. Dear Kafai,


      You are welcome o^_^o!



      From: Sze Ni

      Delete
  21. Dear friends,

    John dipped his hand in the cold water which is a cold object. So his hand's temperature has decreased from the normal body temperature. When he kept his hand in the room temperature water(normal water), his hand gained heat as normal water is much warmer than the cold water. But when Peter dipped his hand in the normal water without dipping in the cold water , his hand must have lost some warmth as it is kept in room temperature.

    From Sanjith

    ReplyDelete
    Replies
    1. From Chin Yin Shuen

      Mmmm.. You're right!


      ^-^

      Delete
  22. Dear friends,

    I think it is because John dipped his hand in the cold water first before he dipped his hand in the warm water but Peter did not dipped his his hand in the cold water first.

    ReplyDelete
    Replies
    1. Dear Li Ting

      To correct your mistake it is actually in the temperature roomed water O^_^O



      Sze Jing

      Delete
  23. Dear Sze Jing,

    Remeber to bring the stamp book.

    Thanks.

    ReplyDelete
    Replies
    1. Stacey,

      You are not allowed to use this page as a chit-chat blog.


      Anonymous

      Delete
  24. This is what I found in Sze Ni's website(that she found).

    The temperature of the hand is raised from normal when it is in the warm water

    This feeling of warmth, then turns to a normal feeling because you leave it in there so long

    When you move this hand into the room temperature water, this lowers the temperature of the hand back back to what it normally is and makes it feel cold because your hand temperature had been raised.

    Thanks. >_< :)

    ReplyDelete
  25. yap Stacey i found that too. Is it found in Sze Ni's website????

    ReplyDelete
    Replies
    1. Dear Felicia,
      what do you mean??





      Sze Jing

      Delete
  26. dear class
    when peter dipped his hand in the basin of cold water he claimed that it feltcold asjohn at firstdipped his hand in the basin of cold water then placed it in the basin of water at room temperature the room temperaturewater lost heat to john's hand so it felt cold . this explains why peter said thatit felt cold

    ReplyDelete
    Replies
    1. From Chin Yin Shuen

      You answer is quite reasonable....Just the sentence too long...:)

      Delete
    2. Dear Sree,

      I think you are correct.

      From:Sze Ni


      Delete
  27. Li ting and Sanjith i think your answers are correct.

    ReplyDelete
  28. I think it is because peter did not dip his hand into the ice water but john did it

    ReplyDelete
  29. From Chin Yin Shuen

    I think the answershould be:

    After John put his hand into the cold water, his hand is cold. then, John puts his hand into the room temprture water. He might have transferred a bit of cold from his hand before he put his hand into the warm water.(this is when his hand turns back to room temperature.)And then, When Peter put his hand in the warm water, the cold was already inside the warm water, making it less warm.This is why Peter felt a little cold.

    ReplyDelete
  30. This comment has been removed by a blog administrator.

    ReplyDelete
  31. (Updated due to some typo error)

    Dear all,

    Thanks for all the interesting inputs and the weblinks.
    I sincerely hope that all of you would have a rough idea of what is actually happening in this situation.

    After looking through some of the inputs, I have decided to provide you with some scientific terms which you can further work on your answers to come up with a more scientifically phrased answer.

    Helping words:
    1) gains / gained
    2) loses / lost
    3) heat

    Awaiting your contribution,

    Mr Ang

    ReplyDelete
  32. Thanks for the iformation Mr.Ang! :D

    ReplyDelete
  33. I think it is "In physics and chemistry, heat is energy transferred from one body to another by thermal interactions.[1][2] The transfer of energy can occur in a variety of ways, among them conduction,[3] radiation,[4] and convection. Heat is not a property of a system or body, but instead is always associated with a process of some kind, and is synonymous with heat flow and heat transfer."
    You can find this on http://en.wikipedia.org/wiki/Heat

    ReplyDelete
    Replies
    1. Dear Kafai
      Thanks for that website! It helped a lot.^_^





      Sze Jing

      Delete
  34. I also think that it is because John first dip his hand in the beaker of water with ice made him cold but he quickly dip his hand in the beaker without ice and than the temperature changes and the filling of the water changes and also the heat will change. ( Sorry if I wrote it weirdly... )

    ReplyDelete
    Replies
    1. Dear Kafai,

      It's not weird. It is correct.

      From Sanjith

      Delete
    2. Dear Kafai,


      I think you are correct.o^_^o



      From:Sze Ni

      Delete
  35. Dear Kafai,
    I agree with your answer(by the way you answer's not weird at all!)




    Sze Jing

    ReplyDelete
  36. Kafai, I agree with your answer. It`s true and thanks for the webpage,anyway.

    ReplyDelete
  37. Felicia,I think your answer is correct but you can phrase it a little bit more differently.

    ReplyDelete
  38. John`s hand is warm beause he touched the beaker with ice but Peter didn`t.

    ReplyDelete
  39. i think is because when John dipped into the water with ice he feels cold so he loses heat but when he immediately dipped his hand into the water with room temperature he immediately feels warm so he gains heat
    Evangeline

    ReplyDelete
    Replies
    1. Hi Evangeline,

      Which comes first? Feeling cold before losing heat or losing heat and therefore feeling cold?

      Think about it. :)

      Delete
  40. It Is Because When John Dipped His Hand In The Beaker With Ice, His Hand Was At Room Tempreature.So John Lost Heat To The Ice To Make It The Same Tempreture,But When He Dipped His Hand In The Beaker Without Ice(Room Tempreture),The Beaker Lost Heat To John's Hand. So When Peter Only Dipped His Hand In The Beaker Without Ice(Now NOT Room Tempreture), His Hand Actually Lost Heat Instead Of Gained Heat.So That Is Why Peter Felt Cold While John Felt Warm.

    ReplyDelete
    Replies
    1. Hi Pashea,

      I like your answer on John's experience.
      By the way, the water in the beaker which Peter dipped his hand into is at room temperature.

      You might want to work a little more on that.

      Thanks.

      Delete
  41. It is because , our body responses to the degree of hotness differently. The degree of hotness also depends on our body tempreture.

    Pi Juan

    ReplyDelete
  42. Dear Zheng Heng ,
    I think your answer is correct. However, to me your answer stated that John transfered some cold water to the water at room tempreture. But the situation did not say that John did anything to the water, it only said that he just dipped his hand into the water.

    Pi Juan :D ( please don't be mad at me for disagreing )

    ReplyDelete
    Replies
    1. Good observation, Pi Juan.
      That is indeed not mentioned.

      Delete
  43. Sorry I think it is disagreeing not disagreing .

    Pi Juan

    ReplyDelete
  44. Yes Pi Juan and hi Danish and Zulhelmi

    ReplyDelete