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alnywk
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do heat will flow from the lower energy to higher/
Yes, energy depends on temperature and on mass, so a large cold mass has more energy than a small hot one.alnywk said:do heat will flow from the lower energy to higher/
This is because the cold object has a much bigger mass than the hot object.pavadrin said:how does something cold have more energy than something hot? isn't t heat a form of energy?
This may be true, but the quantity of energy does not determine how heat will flow. How about an iceberg at absolute 0? The boiling water in the bucket has much more energy than such an iceberg and heat still flows from the boiling water to the iceberg.SGT said:Yes, energy depends on temperature and on mass, so a large cold mass has more energy than a small hot one.
An iceberg has much more energy than a bucket of boiling water. If you throw the water in the bucket on the iceberg, energy will flow from lower to higher.
I am talking of a real iceberg, whose surface temperature should be around 240K or more and a mass of sevral million tons. It certainly has greater energy than the bucket.Andrew Mason said:This may be true, but the quantity of energy does not determine how heat will flow. How about an iceberg at absolute 0? The boiling water in the bucket has much more energy than such an iceberg and heat still flows from the boiling water to the iceberg.
It is the temperature of the two masses which determines the direction of heat flow. Heat energy will only flow directly from hot to cold. It will never flow directly from cold to hot.
AM
I hope you realize that (as AM explained) "heat" naturally flows from hotter to colder (based on a difference in temperature, not total energy content).SGT said:I am talking of a real iceberg, whose surface temperature should be around 240K or more and a mass of sevral million tons. It certainly has greater energy than the bucket.
What I said is that the iceberg contains more energy than the bucket, but heat will flow from the hot, less energectic bucket to the cold, more energectic iceberg.Doc Al said:I hope you realize that (as AM explained) "heat" naturally flows from hotter to colder (based on a difference in temperature, not total energy content).
If you think otherwise, then perhaps you think that if you rest a bucket of water on a big enough iceberg it will come to a boil?
Andrew Mason said:This may be true, but the quantity of energy does not determine how heat will flow. How about an iceberg at absolute 0? The boiling water in the bucket has much more energy than such an iceberg and heat still flows from the boiling water to the iceberg.
It is the temperature of the two masses which determines the direction of heat flow. Heat energy will only flow directly from hot to cold. It will never flow directly from cold to hot.
AM
Well, the question is not all that clear. I interpreted "flow from the lower energy to higher" as "flow from the object whose molecules have lower energy to an object whose molecules have higher energy". Otherwise it is a meaningless question. One may as well ask whether heat can flow from a blue object to a green object. Total energy content (or colour) has nothing to do with heat flow.Doc Al said:Andrew's comment was a response to SGT's comment, which could have been clearer. The OP asked "Does heat flow from low energy to higher?". I think SGT read that question as meaning "Is it possible for heat to flow from low energy to high energy?"
A clearer answer might have been: "The direction of heat flow depends on temperature difference, not on energy content. Heat could flow from low energy to high energy, if the low energy object has a higher temperature."
Exactly. All the more reason to make the answer clear, which you did.Andrew Mason said:Well, the question is not all that clear.
alnywk said:do heat will flow from the lower energy to higher/
The second part of your answer is true, but high temperature means more energy then low only if the two bodies have the same mass. Read the preceding answers.subaru said:no it wouldn't
the rule is unique: the energy flows from the hot object to the cold one
They don't have to have the same mass.SGT said:The second part of your answer is true, but high temperature means more energy then low only if the two bodies have the same mass. Read the preceding answers.
No, they don't, but if they do and if they have the same heat capacity, certainly the hotter body contains more energy than the cold one.Andrew Mason said:They don't have to have the same mass.
AM
I understand what you are saying. But the fact is that the heat flows by molecular collisions and the heat gradually disperses among all three litres. At all times, heat is flowing from matter at high energy to matter at low energy. It does not flow from the hot water to the cold water as a whole. It does it in little bits, and in each little bit the heat flows from high energy to low energy matter.SGT said:No, they don't, but if they do and if they have the same heat capacity, certainly the hotter body contains more energy than the cold one.
Two liters of water at 0 degrees C have more energy than one liter at 100 C.
The mean energy of the molecules in the hot water is greater than in the cold one, but the total energy is greater in the last.Andrew Mason said:I understand what you are saying. But the fact is that the heat flows by molecular collisions and the heat gradually disperses among all three litres. At all times, heat is flowing from matter at high energy to matter at low energy. It does not flow from the hot water to the cold water as a whole. It does it in little bits, and in each little bit the heat flows from high energy to low energy matter.
AM
Heat flows from lower energy to higher energy in accordance with the second law of thermodynamics, which states that heat always flows from a higher temperature to a lower temperature.
The process behind heat transfer from lower energy to higher energy is called convection. This occurs when a fluid, such as air or water, is heated at the bottom and rises to the top, transferring heat to cooler areas.
No, according to the second law of thermodynamics, heat can only flow from a higher temperature to a lower temperature. This is due to the nature of energy and its tendency to disperse and equalize.
The direction of heat flow from higher energy to lower energy is related to the concept of entropy, which is a measure of the disorder or randomness in a system. The second law of thermodynamics states that the entropy of a closed system will always increase, which is reflected in the natural flow of heat from higher energy to lower energy.
The direction of heat flow from lower energy to higher energy can be altered or reversed through the use of external energy sources, such as a heat pump. However, this requires the input of additional energy and does not contradict the second law of thermodynamics.