-1
$\begingroup$

I have just came across a site saying that when we touch a good conductor and if it's temperature is a lower than our body we feel it cold as heat starts flowing from our hands to it. On the other hand if we touch something which is cold but is a bad conductor of heat we will not feel it that cold.

So does this translate to that we will make an error in judging whether the object is really cold or not if it is a worse thermal conductor and it's temperature is considerably lower than our body?

Improve this question
$\endgroup$
3
  • $\begingroup$ You don't feel heat. You feel an increase or decrease in temperature of your skin. It is important to note that heat is not temperature ... it is a form of energy. $\endgroup$
    – David White
    Commented Dec 29, 2017 at 18:19
  • $\begingroup$ yes you are right $\endgroup$
    – Gourab
    Commented Dec 29, 2017 at 18:41
  • 2
    $\begingroup$ @DavidWhite I'm not sure if we can definitively say what humans sense. Seems like it's still a field of study; and they don't fully understand the receptors. The wikipedia articles on it (which probably aren't exactly the greatest source) seem to suggest that the receptors are sensitive to heat and temperature. It also becomes somewhat of a grey area to differentiate the two; because it may detect "temperatures" through some measurement of the heat flow. I can't really think of any other mechanism to measure temperature. $\endgroup$
    – JMac
    Commented Dec 29, 2017 at 18:59

1 Answer 1

Reset to default
0
$\begingroup$

If you touch cotton wool, do you feel hot or cold? I don't think you feel anything, until and unless it's wet.

So, you see that cotton wool is a bad conductor of heat, and it doesn't give you any feeling about its temperature until and unless it's wet, but even in that case, you'll be feeling the temperature if the water and not the cotton wool.

Sensation of temperature or heat, that is, thermal stimuli in Biological terms, truly comes from whether heat flows from your skin to the body or not. If heat flows from your body to the other body, the temperature of your skin gets lowered and you feel cold, the nerves get stimulated by bulboid corpuscles (end-bulbs of Krause) and send signals about the change in temperature, and your brain interprets that the body is cold. Similarly, when you touch a hot body, heat flows from the body to your hand, which raises the temperature of your hand, and your brain interprets that the body is hot.

Just like cotton wool, dry wood will also not give you any such feeling of hot or cold, until and unless it's humid.

Improve this answer
$\endgroup$
2
  • $\begingroup$ I hope the same applies for a thermometer because it detects the temperature by absorbing the heat from the body and causing expansion as in case of mercury thermometers. So this means even thermometers are also inefficient in measuring temperature of a body which is a bad conductor? $\endgroup$
    – Gourab
    Commented Dec 30, 2017 at 7:30
  • $\begingroup$ See, your hand is not a good conductor of heat, so the feeling of heat depends on the conductivity of the body, because the thermal conductivity of your hand won't change. In case of a thermometer, the bulb is itself a good conductor of heat, so the thermal conductivity of the body doesn't matter much. $\endgroup$
    – Wrichik Basu
    Commented Dec 30, 2017 at 8:31

Not the answer you're looking for? Browse other questions tagged or ask your own question.