# What is the fastest way to transfer thermal energy?

1. Nov 28, 2014

### HHH

The fastest way to transfer thermal energy would be through:
B. Thermal conduction
C. Thermal convection
D. Thermal induction

I thought it would be thermal radiation, but my teacher said its conduction. Is he right? Please explain.

2. Nov 28, 2014

### Matterwave

Well, this question really requires some context. Different modes of heat transfer will dominate in different environments. In the usual day-to-day context where things are of roughly room temperature to perhaps the temperature of boiling water, convection will be the fastest way of moving thermal energy around as your teacher says. Radiation is inefficient at low temperatures where things are not radiating very much (you and me, we give off a little bit of thermal radiation in the form of infrared, but not very much).

This should be intuitive and basically you can probably understand this from experience. You stand outside and it's a hot day, what's a great way to cool off? Well a slight breeze will cool you off quite well, much better than you just standing there passively radiating some energy away right?

3. Nov 28, 2014

### HHH

My teacher said conduction.

4. Nov 28, 2014

### Matterwave

Hmm, the usual answer for this question, given normal circumstances is convection. Conduction will win sometimes of course because convection will not arise except under some specific circumstances, like in boiling water, or a wind, or something like that. But when it is present, convection is usually the most efficient/fastest way of transferring heat.

5. Nov 28, 2014

### HHH

Yeah convection makes more sense