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Old Thursday, February 16, 2012
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Smile Difference b/w Heat & Temperature..

Generally, textbooks in Pakistan define Heat and Temperature in a confusing and incomplete way.. The standard definitions of the two are as under..

Heat:
The total kinetic energy of the molecules of a system is called as Heat..
Temperature:
The average kinetic energy of the molecules of a system is called as Temperature..

As compared to a Sea, a cup of Hot Tea has seems to have more heat.. But actually, the sea has more heat than a cup of hot tea.. as the total kinetic energy of the molecules of the sea will be far greater than the total kinetic energy of the molecules of tea.. whereas the average kinetic energy of the molecules of a cup of hot tea is greater than the average kinetic energy of the molecules of the sea.. so the sea has more heat but less temperature as compared to a cup of hot tea..
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Default Heat and temperature are not the same thing!

Quote:
Originally Posted by Da Skeptic View Post
Generally, textbooks in Pakistan define Heat and Temperature in a confusing and incomplete way.. The standard definitions of the two are as under..

Heat:
The total kinetic energy of the molecules of a system is called as Heat..
Temperature:
The average kinetic energy of the molecules of a system is called as Temperature..

As compared to a Sea, a cup of Hot Tea has seems to have more heat.. But actually, the sea has more heat than a cup of hot tea.. as the total kinetic energy of the molecules of the sea will be far greater than the total kinetic energy of the molecules of tea.. whereas the average kinetic energy of the molecules of a cup of hot tea is greater than the average kinetic energy of the molecules of the sea.. so the sea has more heat but less temperature as compared to a cup of hot tea..
I guess bro, you forgot to add something to the definition of temperature . You have elaborated the difference with the example of hot tea and sea quite correctly, but your definition (of temperature) does not conform to it. I think it might be a typo but it makes a big difference. Anyways!
According to your definitions, heat and temperature prove to be the same thing ( ie energy ) in this or that way. Heat and temperature are not the same thing. It's not the average and total kinetic energy of a system that differentiates both. In fact, temperature in itself is not energy at all. Temperature is just a number or measure that is used to determine the average kinetic energy of a system, not a kind of energy in itself. You can say that the average kinetic energy of molecules of a substance is proportional to temperature. The correct definition of both go as:

Heat:
Total kinetic energy of molecules of a substance or system etc is heat.
Temperature:
Temperature is a degree, or number or measure etc to determine the average kinetic energy of a substance or system etc.
OR

The average kinetic energy of molecules of a substance determines the temperature of a substance or a system etc.

To tell more about heat, the heat capacity of a substance depends on the three things
1. its temperature
2. the amount of matter it contains
3. the kind of matter it is made of

Moreover, we have different units of measurement for both heat and temperature. Heat is measured in joules or kilojoules, calories etc. Temperature is measured in Celsius, Fahrenheit, and Kelvin.
So both are inter-related but not identical.
In short, basically, heat is energy and temperature a measure to determine that energy.

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Old Thursday, February 16, 2012
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heat is energy as defined. But temp is totally different thing.its the measurement of that intensity. Degree of hotness and coldness is called temp.sea and cup example show size of object. Each object has its own potential so have different temp acc to potential or energy it has.
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Quote:
Originally Posted by SADIA SHAFIQ View Post
heat is energy as defined. But temp is totally different thing.its the measurement of that intensity. Degree of hotness and coldness is called temp.sea and cup example show size of object. Each object has its own potential so have different temp acc to potential or energy it has.
Yes, temperature may also be defined as degree of hotness or coldness of a substance. The example of a cup full of boiling water and a big kettle full of lukewarm water will be more elaborative here.
A cup full of boiling water has a much higher temperature than a big kettle full of lukewarm water, although the big kettle contains more energy than the cup.
The example given by Da Skeptic is not wrong either, which is very much like the example given by me but the definition of temperature as given by him is wrong.

Regards
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Old Friday, February 17, 2012
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Quote:
Originally Posted by azeegum View Post
I guess bro, you forgot to add something to the definition of temperature . You have elaborated the difference with the example of hot tea and sea quite correctly, but your definition (of temperature) does not conform to it. I think it might be a typo but it makes a big difference. Anyways!
According to your definitions, heat and temperature prove to be the same thing ( ie energy ) in this or that way. Heat and temperature are not the same thing. It's not the average and total kinetic energy of a system that differentiates both. In fact, temperature in itself is not energy at all. Temperature is just a number or measure that is used to determine the average kinetic energy of a system, not a kind of energy in itself. You can say that the average kinetic energy of molecules of a substance is proportional to temperature. The correct definition of both go as:

Heat:
Total kinetic energy of molecules of a substance or system etc is heat.
Temperature:
Temperature is a degree, or number or measure etc to determine the average kinetic energy of a substance or system etc.
OR

The average kinetic energy of molecules of a substance determines the temperature of a substance or a system etc.

To tell more about heat, the heat capacity of a substance depends on the three things
1. its temperature
2. the amount of matter it contains
3. the kind of matter it is made of

Moreover, we have different units of measurement for both heat and temperature. Heat is measured in joules or kilojoules, calories etc. Temperature is measured in Celsius, Fahrenheit, and Kelvin.
So both are inter-related but not identical.
In short, basically, heat is energy and temperature a measure to determine that energy.

Regards
My Dear, Heat is also a measure of the total kinetic energy of the molecules of an object or a system..
Moreover, I have not given the definitions according to my own perception, but the standard and universal definitions.. If u need the reference to it, Inshallah I will provide it.

Quote:
Originally Posted by SADIA SHAFIQ View Post
heat is energy as defined. But temp is totally different thing.its the measurement of that intensity. Degree of hotness and coldness is called temp.sea and cup example show size of object. Each object has its own potential so have different temp acc to potential or energy it has.
If temperature is a measurement of the intensity of Heat, then the units of Heat and Temperature should have been same.. But they are different which shows that they are not the same thing..
As for the degree of hotness or coldness is concerned, this definition is given in our textbooks, which is grossly different to the standard and international defintion.. the standard one I have given above..

Quote:
Originally Posted by azeegum View Post
Yes, temperature may also be defined as degree of hotness or coldness of a substance. The example of a cup full of boiling water and a big kettle full of lukewarm water will be more elaborative here.
A cup full of boiling water has a much higher temperature than a big kettle full of lukewarm water, although the big kettle contains more energy than the cup.
The example given by Da Skeptic is not wrong either, which is very much like the example given by me but the definition of temperature as given by him is wrong.

Regards
In ur first post u have redefined Temperature as a measure of the average kinetic energy of the molecules of a body or an object.. I dont deny it.. But I must say that following the same pattern Heat may also be called as a measure of the total kinetic energy of the molecules of an object..

Quote:
Originally Posted by azeegum View Post
According to your definitions, heat and temperature prove to be the same thing ( ie energy ) in this or that way. Heat and temperature are not the same thing. It's not the average and total kinetic energy of a system that differentiates both. In fact, temperature in itself is not energy at all. Temperature is just a number or measure that is used to determine the average kinetic energy of a system, not a kind of energy in itself.

Temperature is a degree, or number or measure etc to determine the average kinetic energy of a substance or system etc.
OR

The average kinetic energy of molecules of a substance determines the temperature of a substance or a system etc.

To tell more about heat, the heat capacity of a substance depends on the three things
1. its temperature
2. the amount of matter it contains
3. the kind of matter it is made of

Moreover, we have different units of measurement for both heat and temperature. Heat is measured in joules or kilojoules, calories etc. Temperature is measured in Celsius, Fahrenheit, and Kelvin.
So both are inter-related but not identical.
In short, basically, heat is energy and temperature a measure to determine that energy.

Regards
Your definition of temperature as a measure of the heat capacity of a substance is faulty.. This definition means that temperature is the measuring unit of Heat.. See the following definition of Unit of Measurement..
Units of measurement, a standardized quantity of measurement of a quantity
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Last edited by Predator; Friday, February 17, 2012 at 11:34 PM.
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Old Friday, February 17, 2012
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unit separate that's why qk molecules are always in collision. Heat form of energy flow from high conc. To low. So level of heat is'nt same in particular object. So when we want to measure the temp of hand it might be difrnt 4m body. Average temp of human body is 37 coz level or conc . Remain same.that means body metabolism is also in good condition..bt fire ke qarib bethney ce skin ka temp brh jata he. Its mean there is intense heat in skin bt average hotnes of body is 37
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Old Friday, February 17, 2012
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Default Temperature is a measure of heat, not its unit of measurement!

Quote:
Originally Posted by Da Skeptic View Post
In ur first post u have redefined Temperature as a measure of the average kinetic energy of the molecules of a body or an object.. I dont deny it.. But I must say that following the same pattern Heat may also be called as a measure of the total kinetic energy of the molecules of an object..
A measure or a unit of measurement are two different poles apart. You are trying to conflate both with each other, which is not the point I tried to make in my posts above. Understanding the difference between heat and temperature is important but it's not as confusing as you're making it bro.
A measure, or a number or degree are the same thing when it comes to temperature. Temperature is not the unit of measurement of heat but a measure or a number or degree of heat. Or heat is a form of energy and temperature a measure or a number or degree of it. As simple as that! No big deal! But that's not your fault again, because the concept of heat and temperature is mostly confusing because of the facts the following facts.
When heat increases, temperature also increases, and when heat decreases, temperature also decreases. This leads most students to believe that both are the same thing which in fact they are not. Heat, an energy and temperature a measure of it.
Furthermore, both have different units of measurement. Isn't that enough to prove that both are different things?

To further understand and confirm information provided by me, you can visit the following links.

(Read the whole article, esp the last lines very carefully)
How does Temperature Differ from Heat?

(This one is very elaborative; read temperature carefully)
Heat and Temperature

(Read the definition of temperature and its elaboration ahead)
Temperature - definition of temperature

Quote:
Originally Posted by Da Skeptic View Post
If temperature is a measurement of the intensity of Heat, then the units of Heat and Temperature should have been same.. But they are different which shows that they are not the same thing..
As for the degree of hotness or coldness is concerned, this definition is given in our textbooks, which is grossly different to the standard and international defintion.. the standard one I have given above..
Here you did not get Sadia's point too. What she means to say is that heat is an extensive property and thus only a form of energy and temperature is an intensive property and it is more of a quality that describes the intensity with which thermal energy manifests itself.
We have used different words but the sense given by both of us converge at one and the same point.

Quote:
Originally Posted by Da Skeptic View Post
Your definition of temperature as a measure of the heat capacity of a substance is faulty.. This definition means that temperature is the measuring unit of Heat.. See the following definition of Unit of Measurement..
Units of measurement, a standardized quantity of measurement of a quantity
You are again misquoting and misunderstanding me here.
I did not define temperature as the heat capacity of a substance, but tried to prove how heat and temperature were inter-related but not identical. Here is the definition of heat capacity or thermal capacity (C) as taken from Wikipedia.

Heat capacity is the measurable physical quantity that characterizes the amount of heat required to change a substance's temperature by a given amount. In the International System of Units (SI), heat capacity is expressed in units of joule(s) (J) per kelvin (K).

I just made it simple to understand by telling that the heat capacity depends on three things.
1. its temperature
2. the amount of matter it contains
3. the kind of matter is made of.

Very simple!

PS: I have participated in the discussion to correct you, not to beat you. We all are here to learn from each other...
Regards
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Old Saturday, February 18, 2012
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The energy that flows from hot body to cold body is heat, but no matter how 'hot' the object is it does not possess heat.

If you keep a pot on stove, heat goes from flame to the stove, BUT once the heat has reached the pot, the heat converts to K.E. and P.E. in the pot.

It is energy in transit. You cannot say that this box has this amount of heat. When two bodies of different temperatures are put in contact, what flows is heat. But after reaching same temperatures there is no 'heat'. It's all internal energy. So the actual definition is "Heat is the transfer of energy due to temperature difference." Heat is NOT the total of kinetic energy.

Temperature is the degree of hotness or coldness. This 'degree' is commonly measured by our senses, but because of subjectivity, a more uniform way to measure a body's hotness/coldness is required. For this we have thermometer.
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Old Saturday, February 18, 2012
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@Azeegum
M here too to discuss what I think I know, brother.. Yep Heat and Temperature are very closely inter-related, when Total increases, the Average also increases.. What I differ is that Temperature is not a measure of Heat.. An Average can not be the measure of the Total.. I had given the example of Sea and Tea.. Though Sea has less temperature but more Heat as compared to a cup of Hot Tea.. If temperature would have been a measure of Heat, the temperature of the Sea must have been greater than that of a cup of Hot Tea..


Quote:
Originally Posted by SADIA SHAFIQ View Post
unit separate that's why qk molecules are always in collision. Heat form of energy flow from high conc. To low. So level of heat is'nt same in particular object. So when we want to measure the temp of hand it might be difrnt 4m body. Average temp of human body is 37 coz level or conc . Remain same.that means body metabolism is also in good condition..bt fire ke qarib bethney ce skin ka temp brh jata he. Its mean there is intense heat in skin bt average hotnes of body is 37
This example also shows that Temperature is not a measure of Heat..Again referring to the Same example I gave earlier, a Sea has more heat but less temperature..

Quote:
Originally Posted by chemguy View Post
The energy that flows from hot body to cold body is heat, but no matter how 'hot' the object is it does not possess heat.

If you keep a pot on stove, heat goes from flame to the stove, BUT once the heat has reached the pot, the heat converts to K.E. and P.E. in the pot.

It is energy in transit. You cannot say that this box has this amount of heat. When two bodies of different temperatures are put in contact, what flows is heat. But after reaching same temperatures there is no 'heat'. It's all internal energy. So the actual definition is "Heat is the transfer of energy due to temperature difference." Heat is NOT the total of kinetic energy.

Temperature is the degree of hotness or coldness. This 'degree' is commonly measured by our senses, but because of subjectivity, a more uniform way to measure a body's hotness/coldness is required. For this we have thermometer.
Dear Bro, we have not said that Heat is something different from Energy.. We know that Heat is a form of Energy..
The transfer of energy is not Heat, it is the flow of Heat Energy..
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Last edited by marwatone; Friday, February 24, 2012 at 03:02 AM. Reason: Posts merged.
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Old Saturday, February 18, 2012
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@Da Skeptik
The average K.E. is independent of the size of the body. Even though the sea has trillions of molecules, when you take an average, it is the median K.E. of only one molecule. You see, the 'sea' has much greater 'total' K.E., but its average is paltry.

What are you trying to ask anyway
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