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[Official] The Doubts thread for General Science

edited March 2015 in Science & Tech
Hi friends ,This thread we wil be discussing mainly on day to day activities and observation, finally interpretation of ones action in relation to surroundin biosphere .Plz share ur questions with solutions to enrich ourselves to reach our destiny .

1.What r the exampls of chemical reaction ,is this a permanent or temporary reaction ?
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Comments

  • Wht are the reasons for increasing size of water bubble from down of any water body to top ?


  • 1.What r the exampls of chemical reaction ,is this a permanent or temporary reaction ?
    -Permanent
    - Examples - oxidation of iron , photosynthesis , any combustion , usage of soaps and detergents.
    @nuralain but there are many chemical reaction which are reversible in nature and can be called temprary as a slight change in condition will start backward reaction..usually when product formed is unstable....so i think it is not correct to say that chemical changes are permanent...they are normally permanent is more correct..
  • edited March 2015
    @Nuralain i searched on the net..there are few reaction which are reversible..i will post link tomorrow..and that change of condition logic,then even in physical changes,some variable changes to reverse the change..for example when water evaporates into vapour,it will condense into water only when either temperature is decreased or relative humidity increases...something will have to change to revert it back...
  • @Nuralain oh i missed that i agree part...cool..we are on same page on this one.. :)
  • hhehhe thanx nuralain..
  • edited March 2015
    to anyone who has a doubt...here is how i try to differentiate-every substance has basic repeating strucuture which forms the matter..for eg.water has h2o molecule as repeating building unit..water is just many h2o molecules arranged...in physical change,only this arrangement will change..in solid very closely packed,in liquid little less tightly and in gases free....in chemical chnage,this repeating unit changes and so we say new product is formed...for eg mgO+h2O->mg(oh)2...now repeating unit in product is new molecule and hence new product is formed....
  • The velocity of sound how it depends on temparature of surrounding medium ? can any one explain .
  • The velocity of sound how it depends on temparature of surrounding medium ? can any one explain .
    Bhai I would like to share you two basic rule of Physics --

    1) Temperature is inversely proportional to density ;
    2) Velocity of Sound varies inversely as the square root of density ;
  • The velocity of sound how it depends on temparature of surrounding medium ? can any one explain .
    One more thing bhai...
    Speed of sound does not only varies with density and temperature ...

    You know , Speed of sound in Air ( at 20 degree celsius ) is 343 m/sec ....And Speed of Sound in Water at the same temperature is =1482 m/sec...

    So if we proceed by the aforementioned comment by me and @Nuralain , then of course the density of Air Molecules is very less as compare to water , then at the same temperature the Speed of Sound should have been higher in the Air ....But it is not the case in actual.

    Reason- the Speed of sound also directly varies with the Bulk Modulus of media ...

    What is Bulk Modulus = it is the property that determines the extent to which the element of a medium changes in volume when the Pressure on it changes ....Its unit is same as that of Pressure ( Newton/ meter square )....

    And the bulk Modulus of water is far greater than the Air , so at the same temperature , Speed of Sound is greater in Water as compare to Air ...

    Actually , Speed of any transverse wave varies directly with the square root of Elastic Property of the medium( to store potential energy ) and and it varies inversely with square root of the Inertial Property of the medium ( to store kinetic energy )..
  • can anyone elaborate various types of mobile softwares like -android,kitkat,lollypop,macpro,etc.
    have heard a lot of fancy names,but have little knowledge!
    "i am the guy doing my job,you must be the other guy."
  • edited March 2015
    can anyone elaborate various types of mobile softwares like -android,kitkat,lollypop,macpro,etc.
    have heard a lot of fancy names,but have little knowledge!
    :-? :-? :-? .....I do not even have the smartphone bhai, let alone hearing about the fancy names ....still I am using Nokia phone --Nokia 1110....

    Its not that I can't purchase any i-Phone or Samsung's Smartphone ....But I know i will not use them , until my selection, so no use of these gadgets to me ....

    Regarding you question --- :-?? :-?? :-?? :-??
  • ^ Windows 8 aa gaya hai kya ???......

    Arey I am still using Windows 7 .....

    Such a "dhakkan" I am yar...
  • what is the major difference between android and windows (nokia/microsoft)phones?
    "i am the guy doing my job,you must be the other guy."
  • what is the major difference between android and windows (nokia/microsoft)phones?
    Android is like a vanilla ice cream owned by Google, so every other firm takes this vanilla ice cream and adds chocolates, strawberries and other things for example Samsung(TouchWiz), HTC(Sense) so on and so forth. :D

    Windows mobile OS is proprietary in nature which implies that Microsoft owns the Windows Mobile OS.
  • how does these led bails work ? they light up as soon as they are hit by ball.(w.cup cricket)
    i am sure everyone has seen them.
    "i am the guy doing my job,you must be the other guy."
  • How trillions of Nutrinos pass through human body every second ?
  • edited March 2015
    how does these led bails work ? they light up as soon as they are hit by ball.(w.cup cricket)
    i am sure everyone has seen them.
    In these LED zing bails; Low voltage batteries are there in the bails and the stumps, so that is the power source. An inbuilt sensor can detect the slightest impact. When Kohli would be out, the bails will flash those lights. Immediately, as soon as 1/1000 of a second , the sensor in the bail sends radio signal( with the help of a microcontroller ) to the stumps which also start glowing.
    how the hell do you know so many things?
    :O :-/
    "i am the guy doing my job,you must be the other guy."
  • why we feel so cool under tree ...
  • How trillions of Nutrinos pass through human body every second ?
    Nuetrinos are charge nuetral particles, and interact very weakly with matter. For a nuetrino to affect matter/human body, they must intract through some significant force. That explains how they are able to penetrate matter and human body. In fact that is the reason why nuetrino labs are underground.
    What doesn't kill u, makes u stronger.
  • How trillions of Nutrinos pass through human body every second ?
    Nuetrinos are charge nuetral particles, and interact very weakly with matter. For a nuetrino to affect matter/human body, they must intract through some significant force. That explains how they are able to penetrate matter and human body. In fact that is the reason why nuetrino labs are underground.
    bt they lack electric charge ..
  • why we feel so cool under tree ...
    1. Shade
    2. Transpiration results in cooling.

    @asdfghjkl check out the first line of the last answer.
    What doesn't kill u, makes u stronger.

  • BTW guys, since you were talking about android/ windows and other platforms - if you are interested in how technology is revolutionising the way services industry works (specifically on mobile interface), check out this talk by Hugo Barra (erstwhile Google Android head and now Xiaomi's main guy) when he tells how China has gone bullish!

    Promoter @ Civilsdaily's android app | To be human is to be curious, childlike, complex and immoral.
  • why we feel so cool under tree ...
    1. Shade
    2. Transpiration results in cooling.

    @asdfghjkl check out the first line of the last answer.
    That means transiration is heat absorbing process .

  • ^Yes
    What doesn't kill u, makes u stronger.
  • when working refrigerator opened in one corner of closed room then temparature of room increases ,why so ..
  • A piece of copper and a piece of glass are heated at same temparature after some time copper will be more hotter than glass ?

    ANS :Is this becz of Specific heat of copper is more than glass ,plz correct me if im wrong .
  • Any sane explanation for the Coriolis Force/Effect?
    Sub Query: Reasons for tropical cyclones not forming near the equator?
  • Any sane explanation for the Coriolis Force/Effect?
    Sub Query: Reasons for tropical cyclones not forming near the equator?

    becz at equatorial region there is no corialis force .

  • edited March 2015
    when working refrigerator opened in one corner of closed room then temparature of room increases ,why so ..
    Because a refrigerator motor extracts heat from the freezing chamber and releases it to the outer atmosphere ..
    A piece of copper and a piece of glass are heated at same temparature after some time copper will be more hotter than glass ?

    ANS :Is this becz of Specific heat of copper is more than glass ,plz correct me if im wrong .
    Somewhat it is .....but I have tried to explain it from Current electricity point of view..

    It is because of Free electrons and bounded electrons ...
    Now what are free and bounded electrons-

    Free Electrons - Electrons which are loosely bound to the nucleus are Free electrons . These electrons are free enough so as to freely move inside the material , but at the room temperature they do not eject out of the material.

    Bound electrons - The electrons in an atom which are comparative more strongly bounded to the nucleus are Bound electrons..

    and Copper is a conductor ( in conductor number of free electrons are very high ) and Glass is an insulator ( in an insulator , number of electrons are negligible ) ....

    and when copper and glass are heated at the same temperature , due to availability of more free electrons in copper ( because it is a conductor and for current flow free electrons are necessary) and heat is directly proportional to the square of current flow ......Copper ultimately gets more hotter than the glass.
  • Any sane explanation for the Coriolis Force/Effect?
    Sub Query: Reasons for tropical cyclones not forming near the equator?
    it comes from a derivation. but from now you can understand, that a body moving on a rotating body experiences such a force. (so does winds and water - since they are moving (read have velocity) on the rotating earth.

    ignore this if u dont have a background in science:
    the direction is given by w(x)v (cross product. where w is the angular velocity of rotating body (earth) and v is the velocity of the body moving on that rotating body (wind/water)

    apply this cross product on equator and u will understand why does it not act on the equator.

    ps: if u find it too technical, u can be happy with the first half of the answer.
    What doesn't kill u, makes u stronger.
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