Question

Why are glass tumblers made of thin glass?

Answer 1

Hint: In order to solve this question we need to understand heat and its method of transition. Heat is the thermal energy which only flows due to temperature difference between the system and surrounding. There are three methods of heat flow, one is conduction in which heat flows due to atoms vibration and exchange of heat occurs through phonons of vibration, another is convection in which heat transports through matter exchange like convection current flows in summer, and third is radiation in which heat flows due to exchange of photons in this heat flow like in blackbody radiation.

Complete answer:
Frequent or energetic atoms absorb most of the thermal energy provided to them and hence they vibrate with lesser energy which in turns affect the rate of exchange of phonons and hence glass is a bad conductor of heat.

Now when this heat generated in glass it flows slowly so if a glass is thick then heat may affect the parts of glass in the middle while flowing because of its less rate of flow so glass may have a crack but if glass is thin enough then heat does not find more space and glass could be saved. That’s why glass tumblers are made up of thin glass so heat does not affect them.

Note: It should be remembered that phonons are quantum particles and they are analogous to photons in light, it was proposed in the Kronig-Penney model of electrons. Also mode of heat transition in glass is conduction as here only energy transports without exchange of matter itself. While convection involves matter exchange.