Why do hot things seem to get hotter the longer I hold them?

Question

I mean like mugs full of hot water and stuff like that.
I undestand they don’t actually get any hotter than they already are, so why does it feel like that?

In: 109

Answer 1

We all know objects are made up of atoms and molecules. These atoms and molecules constantly move around or ‘jiggle’ inside and on the surface of the object. This ‘jiggling’ decides the energy or the ‘excitement’ of the object.

When we say an object is cold, it means atoms and molecules are stable and are not jiggling. Hence, water turns solid when it gets cold. On the other hand, when an object is hot, it means these atoms and molecules are really excited and are ‘jiggling’ a lot. The higher the temperature of the object, the faster it’s atoms jiggle or vibrate.

So how does heat transfer take place? Let’s say I bring a vibrating ball in contact with another stationary ball (both balls are fixed in place and are not free to move, just can vibrate). The vibrating ball is going to keep hitting the stationary ball and transfer its energy so both balls start vibrating.

Similarly, let’s say I place a ice cube on a hot pan. The atoms of the pan are vibrating intensely, and these atoms keep hitting (literally) the more or less stationary atoms of the ice cube resulting in the atoms of the ice cube to start vibrating. This is what you will see if you use a powerful microscope to observe heat transfer. It is literally the transfer of mechanical energy (or physical movement energy) from one body to another.

When you touch a hot object, the atoms of the object keep hitting your cells with extremely high intensity. Imagine thousands of hammers hitting each cell really hard and extremely fast. This hammering damages our cells which is what we call a burn.

To answer your question, since hot objects literally hammer your cells, you will start to feel more painful the longer you hold them. Of course this is true for moderately hot object. Boiling water is so hot that the hammering effect is extremely strong and it can instantly burn you.

Hope this answers your question.

Edit: Credits to Richard Feynman for this amazing explanation of heat transfer.