# Temperature is the measure of average kinetic energy of the molecules

1. Dec 29, 2009

### phymatter

temperature is the measure of average kinetic energy of the molecules of a gas , also temperature is the measure of hotness or coldness of a body , but how does this molecular motion motion produce heating effect that we can feel??????????!!!!!!!!!!!

2. Dec 29, 2009

### elven

Re: heat

The friction caused by the molecular motion causes heat.

3. Dec 29, 2009

### Andrew Mason

Re: heat

Three possible ways: conduction, convection and radiation.

Heat conducts from the hot body to your hand when there is mechanical contact between your hand and the body. The molecules in the body physically impact the molecules in your hand and cause them to move more rapidly. This causes heat to transfer to your hand.

The air around the hot body conducts heat from the body. The air warms. This causes it to be more buoyant so the warm air rises. Cooler air comes in to replace it and it too heats up on contact. You can feel this warm air as it circulates around the room.

A body at a temperature $\Delta T$ above the temperature of its surroundings, will radiate more energy than it absorbs. Your hand may absorb some of this radiation (infra-red) and feel heat.

AM