Newton's Law of Cooling & Specific Heat Capacity

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SUMMARY

Newton's Law of Cooling is mathematically expressed as TObj = (TInitial - TEnv)e^(kt) + TEnv, where k is a material property. The specific heat capacity (C) is defined in the equation Q = mCΔT, indicating that both k and C are intrinsic properties of materials. The discussion reveals that while k is related to the specific heat capacity, it does not require a draft for accuracy; however, a draft enhances the precision of measurements. The relationship between k and C suggests that k can be influenced by the specific heat capacity and mass of the object.

PREREQUISITES
  • Understanding of Newton's Law of Cooling
  • Familiarity with specific heat capacity and its equation Q = mCΔT
  • Knowledge of temperature difference and heat transfer principles
  • Basic grasp of logarithmic functions and their application in physics
NEXT STEPS
  • Research the derivation and applications of Newton's Law of Cooling in various materials
  • Explore methods for calculating specific heat capacity using calorimetry
  • Investigate the impact of forced convection on heat transfer rates
  • Study the relationship between thermal conductivity and specific heat capacity in different materials
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Physics students, engineers, and professionals in thermodynamics who are looking to deepen their understanding of heat transfer principles and the relationship between material properties.

Bradley Sigma
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Newton's Law of Cooling basically states (I believe):
TObj = (TInital-TEnv)ekt + TEnv
where k is a property of the material.

In the equation:
Q=mCΔT
Specific heat capacity, C, is also a material property.

So here's my question:
Is there a relation between Newton's Law's k and the specific heat capacity of the material?
Also, I'm in a debate whether Newton's Law requires a draft to be accurate. Any information either way would be useful.

Thanks
 
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Bradley Sigma said:
Newton's Law of Cooling basically states (I believe):
TObj = (TInital-TEnv)ekt + TEnv
where k is a property of the material.

In the equation:
Q=mCΔT
Specific heat capacity, C, is also a material property.

So here's my question:
Is there a relation between Newton's Law's k and the specific heat capacity of the material?
Also, I'm in a debate whether Newton's Law requires a draft to be accurate. Any information either way would be useful.

Thanks

Yeah ,

http://www.tutorvista.com/content/physics/physics-iii/heat-and-thermodynamics/Newtons-law-cooling.php

Yeah , it requires draft to be "more" accurate...

I would like other members as well to post their views...
 
Bradley Sigma said:
Newton's Law of Cooling basically states (I believe):
TObj = (TInital-TEnv)ekt + TEnv
where k is a property of the material.

In the equation:
Q=mCΔT
Specific heat capacity, C, is also a material property.

So here's my question:
Is there a relation between Newton's Law's k and the specific heat capacity of the material?

Thanks
The general law states that the rate of heat transfer is proportional to the temperature difference and the area of contact.
Solving for a body cooling in some environment with fixed temperature produces an expression like the one you propose. Only that for cooling the exponent is negative. Your solution correspond to a temperature that increases indefinitely in time, unless you assume k<0.
Indeed the time constant in the exponent depends on the specific heat capacity of the body (and its mass too).
 
It's not that it requires a draft, merely that what it's in contact with has effectively a constant temperature. In air, some forced draft, rather than mere convection, will certainly be needed. But in principle it could be encased in a solid with a very high specific heat.
The concept of a Tobj also suggests the object maintains a uniform temperature, which would imply a very high conductance. In practice, the temperature profile through the object will tend to change over time. It is probably not right to take an average temperature and expect the equation to work exactly, but I could be wrong.
 
sankalpmittal said:
Yeah ,

http://www.tutorvista.com/content/physics/physics-iii/heat-and-thermodynamics/Newtons-law-cooling.php

Yeah , it requires draft to be "more" accurate...

I would like other members as well to post their views...

Newton's Law of cooling can also be stated as
ln(TObj-TEnv) = kt+c
k can therefore be found by finding the gradient of the trend line of the natural logarithm of the difference in temperature between object and the environment as a function of time.
However, would I be correct in thinking that something similar cannot be done to obtain the specific heat capacity, as your link states k=K/mC, for which the mass can easily be found, but as both K and C are unknown, they cannot be determined to a specific value. I know that there are other ways of determining specific heat capacity, I'm just wondering if it can be done using Newton's Law of Cooling.
 

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