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When I look at the digital thermometer or read the current temperature in my area, am I looking at a value based on the heat of the area or something else? If it's not based on actual heat, could this be the reason why two different parts of the world can report the same temperature but have a different response from the citizens.

i.e. roads melting in an uncomfortable but otherwise not severe temperature by the standards in another country, chilly temperatures by Australian standards being treated as warm weather in England, etc.

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Heat and temperature are 2 different things. Heat is related to the magnitude of kinetic energy an object has.

Temperatures on the other hand means the average kinetic energy of a particle inside an object.

From this you can see that the bigger, denser... an object is, it will have more heat than the smaller object even though they are at the same temperature.

Heat is the ammount of total kinetic energy of a rest mass while temperature deals in the average kinetic energy of a rest mass.

What you see measured in the usual sensors is the temperature, not heat.

The different response of people is based on their everyday experience.

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  • $\begingroup$ I know they're different things, which is the point of the question. I'm not convinced the different response is entirely based on everyday experience. I can bite into different foods, all with the same temperature but with different heat. The hotter ones will feel hotter than the cooler ones. Despite them all having the same temperature. Or is my understanding of heat and temperature wrong? $\endgroup$ – Space Ostrich Feb 3 '17 at 11:47
  • $\begingroup$ I think you are confusing a few things. The food example is due to something different. Let's say you heat up a styrophome and metal both to 100 degrees. The average molecule energy of both is the same. Which one are you more afraid to touch? I guess your answer Will be metal. The reason for this is that different materials have different conductivity of heat. That means they give or gain heat faster. So if you touch metal it Will conduct a lot of heat to you in very short time, while styrophome Will take a lot longer to do so. Also styrophome is a lot lighter so it has less heat capacity. $\endgroup$ – MaDrung Feb 3 '17 at 11:53
  • $\begingroup$ So different foods at same temperature give different termal responses to you because of speed of different heat conduction. When you say hotter and cooler ones you can only relate to temperatures, not heat. The temperature tells you from which material Will the heat flow. So let's say the temperature of styrophome is 351 K and the temperature of metal is 350 K. The heat would flow from styrophome to metal. Even though you would still rather touch styrophome than metal because of it's slower heat conduction. :) $\endgroup$ – MaDrung Feb 3 '17 at 11:56
  • $\begingroup$ Same metals Will melt at same temperatures no matter if they're in Australia or United Kingdoms or USA. $\endgroup$ – MaDrung Feb 3 '17 at 11:58
  • $\begingroup$ Fair enough, I guess my understanding of heat energy was flawed. $\endgroup$ – Space Ostrich Feb 3 '17 at 12:02
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There are a couple reasons.

A big one is obviously the difference between heat and energy, as MaDrung already talked about quite a bit.

If you're familiar with electric circuits, I will try and expand upon temperature and heat transfer with a circuit analogy. In a circuit the current flows across a potential difference given by voltage. The current flowing depends on voltage difference and the resistance.

For the heating analogy; voltage is the same as temperature, and heat transfer is the same as current. The resistance to heat transfer depends on the real situation in the heat transfer medium. If two objects are at the same temperature; there should be no heat transfer between them. The amount of heat transfer is proportional to temperature, and is also inverse proportional to resistance.

When our bodies feel hot or cold, they aren't actually feeling the temperature. They are sensing the heat gain or heat loss. The heat loss depends on more than just temperature; it also depends on that "resistance". The resistance is changed by many things including how many layers of clothes you have on, how windy it is, and how humid the air is. This is one reason why two places with the same temperature may feel different.

Another big reason is the climate you live in and human psychology. If your average temperature is warm year round (like Australia) then 15 C isn't really a nice day (this also depends on seasons). On the other hand in England, 15 C could be a reasonable temperature, especially if it was near winter; then it could be an unusually warm day. It's like going down south in the winter for vacation. It seems really warm to you; but it's regular weather for the locals.

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