# Homework Help - Freezer

1. Feb 17, 2008

### sdb16

Please can anyoine explain to me why a freezer is located at the top of a unit when i understand that hot air rises.

I have searched for some answers but cannot find an explanantion.

Thanks
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

2. Feb 17, 2008

### physixguru

When air becomes hot it expands and so the density decreases.and hot air goes up.just the opposite thing happens when air is cooled..It contracts,its density is increased and it comes down.So when the freezer cools down the top layer of the air in the refrigerator,the cold air comes down slowly.This process continues and the whole of the refrigerator remains cool.For the same reason,you must fix the AC higher than your bed level or body level to really enjoy the coolness.

3. Feb 17, 2008

### marlon

I would say this : when air is cooled, it comes down (you know the reason why, right ? . So putting the freezer on top makes sure that the cooled air has plenty of room to come down. This way, the refrigerator stays cool.

marlon