Heat and max temperature Problem

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Homework Help Overview

The discussion revolves around a temperature comparison problem, specifically whether a maximum temperature of 28°C is twice as hot as 14°C. The original poster presents equations related to heat transfer but expresses uncertainty about their application to this context.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to analyze the problem using heat equations and considers the energy absorbed by a mass at different temperatures. They question the validity of their reasoning and whether the problem is designed to be misleading.

Discussion Status

Participants are exploring the concept of temperature scales, particularly the distinction between Celsius and Kelvin. Some provide insights into absolute zero and the implications for temperature comparisons, while others reflect on the simplicity of the problem after further discussion.

Contextual Notes

There is a focus on the relevance of temperature scales in the discussion, particularly the misconception regarding Celsius as an absolute scale. The original poster's approach involves theoretical calculations that may not align with the fundamental principles of temperature measurement.

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[SOLVED] Heat Problem

The question is:

If today's maximum temperature was 14°C and tomorrow's maximum is expected to be 28°C, will tomorrow be twice as hot as today. Explain your answer.

The only equations known are Q=mcΔT, and Q=ml
Where Q= energy in joules. m=mass in kg, c= specific heat capacity [to 3 decimal places], ΔT= the change in temperature in either kelvin or Celsius, l= latent heat [also to 3 decimal places]

However I am not limited to these equations, just expected to use them. Use of other equations is fine, so long as they are within reason.

My train of thought was that, I need to find out and compare how many watts of heat will be absorbed by an identical body of mass over the same period of time at the two different temperatures, i just don't know how. I also think that this is one of those questions designed to trick, or at least make you really think. So I think that the short answer to the question is no, I just can't prove this right or wrong.

I have tried taking a theoretical 1kg aluminium block and putting them into each of the temperatures resulting in these equations:

8.90e+3*14=124600
8.90e+3*28=249200
as 249200 is 2*124600 then it is twice as hot

However I do not think this is right as these values are the amount of energy required to make this temperature change. Am I on the right track, or am I nowhere near the answer?
 
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Think about this: is zero degress C the bottom of the celsius temperature scale?
 
No it isn't, -273°c is. Can you please explain the relevance of this though? I just chose 0°c as a point from which the blocks would get heated. If you convert the temperatures to kelvin you get exactly the same results.
 
14\circC is 14 + 273 = 287 degrees above absolute zero. 28\circC is 28 + 273 = 301 degrees above absolute zero.

Now \frac{301}{287} = about 1.05, and so 28\circC is about 5% hotter than 14\circ, not twice at hot.

A temperature of 2(287) - 273 = 301\circC is twice as hot as 14\circC.

The celsius scale is not an absolute T scale. The kelvin scale is. 0K is absobute zero and so, for example, 300K is twice as hot as 150K.
 
Ok, I was just trying to over complicate things, as usual. Now that I look back at the problem I see how simple it is. Thanks for your help, no doubt I will call on it again some time in the future.
 

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