2007-02-07 21:39:50 · 8 answers · asked by andrew s 1 in Environment
heat is a description for energy, a hot substance has had more energy transferred into it which excites the particles.
with gases this causes the volume of the gas to expand.
(think of this like a school playground, make all the kids stand still in a tight group and they are a solid, let them spread out and play and they are a gas, the more energetically they play, the more space they need)
obviously an expanded volume of gas will be lighter for a given area than a concentrated volume of gas, so the lighter (hotter) gas is displaced upwards by the heavier (colder) gas
2007-02-07 21:58:57 · answer #1 · answered by only1doug 4 · 0⤊ 0⤋
Heat doesn't rise. It is hot air that rises. The reason being that when a gas is heated it expands and becomes lighter per unit volume. Heat is an energy and radiant heat is as effective in all directions.
2007-02-08 05:11:35 · answer #2 · answered by Professor 7 · 0⤊ 0⤋
The easiest explanation is about equilibrium. The basic concept of equilibrium is that molecules flow form area of higher concentration to areas of lower concentration.
When you heat air the molecules are more active than their cooler cousins and therefore the molecules are less tightly packed and not in equilibrium.
The higher you go the less densely packed the air molecules are which is caused by the effects of gravity on all the molecules in the air.
So in an effort reach equilibrium the hot, less dense, air rises to the less dense air at higher altitudes, until equilibrium is reached at which time the air will no longer rise.
The concepts of equilibrium, density, and buoyancy are all closely related in that they are all concerned with mass per unit area. These concepts are what causes hot air to rise, hot air balloons to rise, and boats to float.
2007-02-08 01:36:11 · answer #3 · answered by Brian K² 6 · 0⤊ 0⤋
Heat travels from hot to cool. It rises because the heat source is at the bottom and cooler air or medium is above it.
2007-02-07 21:45:24 · answer #4 · answered by Anonymous · 0⤊ 3⤋
Heat dosent rise. Hot air dose and thats because hot air is lighter. think about how wood floats and you'll get the idea
2007-02-07 21:44:49 · answer #5 · answered by machetemachine 1 · 0⤊ 2⤋
It is less dense than air, therfore it rises through convection.
2007-02-07 21:43:38 · answer #6 · answered by blue1 3 · 2⤊ 0⤋
every thing that's hot always rises like cakes
2007-02-07 21:49:14 · answer #7 · answered by Anonymous · 0⤊ 2⤋
BECAUSE WARM AIR IS LIGHTER THAN COLD AIR
2007-02-07 21:43:06 · answer #8 · answered by PuNkY n PeRkY..x 2 · 2⤊ 1⤋