Can Heat Transfer Occur Unevenly in a System with Constant Temperature?

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In summary, the question can't be answered without more information about how the temperature change occurs and how B and B' are being cooled.
  • #1
fluidistic
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I just thought about the following case and I have a doubt.
Say I have a system like this : B-------A-------B' where A is a continuously heated metal so that it's temperature remains constant with time. Imagine there's a fluid like air between A, B and B' so that A transfers heat to B and B' via convection. Suppose that the temperature of B is almost the one of A and the temperature of B' is much lower than the one of A. Suppose also that B and B' don't transfer heat to each other (because they are too far from each other).
Last supposition : B and B' are the same material, say a metal (whose specific heat is a constant).
My question is : If B get heated by 1K, does B' also get heated by 1K? I was tempted to say yes because they have the same specific heat but now I have doubts. I think that maybe B' can be heated more than 1K while B got heated by 1K, because the temperature of B is closer to the one of A than the one of B' is.
Maybe I should write down some equations, but I'll soon learn about gradient in cases similar to this one.
Thanks in advance.
 
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  • #2
fluidistic said:
My question is : If B get heated by 1K, does B' also get heated by 1K?

This question can't be answered unless you specific how the change in temperature occurs and how B and B' are being cooled. So far you've described a steady-state system where B-------A-------B' is symmetric up to a point; however, energy is being removed more rapidly from B' than from B (that's the only way to explain the difference in temperature of two identical materials).
 
  • #3
Mapes said:
This question can't be answered unless you specific how the change in temperature occurs and how B and B' are being cooled. So far you've described a steady-state system where B-------A-------B' is symmetric up to a point; however, energy is being removed more rapidly from B' than from B (that's the only way to explain the difference in temperature of two identical materials).

Ok I understand. I precise : the change in temperature occurs by convection due to air between A and B, and A and B'. And initially B and B' have different temperature. For example B and B' could have been cooled/heated in another systems and then put in the one I described.
I realize that if B is heated by 1K then B' will be heated by more than 1K. However I don't know why since they have the same specific heat.
Why does B receive less energy from A than B' does? Because of the slight difference of temperature?
My question is also equivalent to ask why a very hot body in air loses its heat quickly and then less and less quickly.
Is it because of the gradient of temperature? Newton's law of cooling? Are they (Newton law of cooling and the gradient) related?
I don't understand why the process of change of temperature works like it works.
By the way thanks for helping me.
 
  • #4
OK, got it. The general principle is that energy moves down a steeper gradient faster. Well, actually energy is moving everywhere all the time, but it's unlikely for it to move from a colder to a hotter material (Second Law). The unlikeliness increases with increasing temperature difference. So as a gradient increases, energy transfer down the gradient becomes more and more favorable, which translates into an increasing transfer rate. Yes, this is the origin of Newton's cooling and Fourier's conduction laws.
 
  • #5
Mapes said:
OK, got it. The general principle is that energy moves down a steeper gradient faster. Well, actually energy is moving everywhere all the time, but it's unlikely for it to move from a colder to a hotter material (Second Law). The unlikeliness increases with increasing temperature difference. So as a gradient increases, energy transfer down the gradient becomes more and more favorable, which translates into an increasing transfer rate. Yes, this is the origin of Newton's cooling and Fourier's conduction laws.

Thank you very much for the good explanation.
 

1. How is heat measured?

Heat is typically measured using a thermometer, which measures the temperature of an object. The unit of measurement for heat is degrees Celsius (°C) or degrees Fahrenheit (°F).

2. What is the difference between heat and temperature?

Heat is the transfer of thermal energy from one object to another, while temperature is a measure of the average kinetic energy of the particles in an object. In other words, heat is the movement of energy, while temperature is a measure of the amount of energy present.

3. How does heat transfer occur?

Heat can transfer through three main mechanisms: conduction, convection, and radiation. Conduction is the transfer of heat through direct contact between two objects, while convection is the transfer of heat through the movement of fluids. Radiation is the transfer of heat through electromagnetic waves.

4. What factors affect how well I understand heat?

The factors that affect how well you understand heat include your level of education, background knowledge in science and physics, and your ability to grasp complex concepts. It also depends on how much time and effort you put into studying and learning about heat.

5. How can I improve my understanding of heat?

You can improve your understanding of heat by studying and learning about the different properties and behaviors of heat through textbooks, lectures, and hands-on experiments. It's also helpful to ask questions, seek clarification, and practice problem-solving to solidify your understanding.

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