Why do Metals Feel Cold or hot to the Touch?

Most recent answer: 11/16/2016

Q:
why do metallic objects feel hotter / colder than their neighboring non-metallic objects (such as plastics or wood) subject to the same sunlight and environmental conditions? Do metals' temperature rise above the ambient temperature, and if so, why and how?
- Anonymous
A:

In general, metals feel colder or hotter to the touch than other materials at the same temperature because they're good thermal conductors. This means they easily transfer heat to colder objects or absorb heat from warmer objects. Your skin can't actually detect the temperature of other objects—it only senses its own temperature. When you touch a piece of metal that is colder than your hand, your fingers rapidly lose heat and feel cold—and the opposite happens when you touch metal that is hotter than your hand. Thermal insulators like plastic and wood don't transfer heat as easily.

Some metals may also get hotter faster compared to other materials. Metals tend to have a small specific heat capacity, which is a measure of how much energy needs to be added to a material to raise its temperature by 1 degree. A material with a smaller heat capacity will reach a higher temperature after the same amount of energy is added compared to a material with a larger heat capacity. Polyethylene, a common plastic, has more than twice the heat capacity of most metals. Water also has a very large heat capacity.

Rebecca H.


(published on 11/16/2016)