2007-04-24 15:20:38 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Other - Science
Heat causes the fluid to expand (because the molecules are more energetic, they bounce father away from each other when they collide). When the fluid expands, it becomes less dense, so it is pushed upward by the more dense (cooler) fluid surrounding it.
2007-04-24 15:26:54 · answer #1 · answered by Randy G 7 · 0⤊ 0⤋
In warmer fluids(gases and liquids) the molecules are moving faster and farther apart. This makes them less dense. Things which are less dense than the surrounding area rise. Things which are more dense will sink.
2007-04-24 22:41:09 · answer #2 · answered by science teacher 7 · 0⤊ 0⤋
Because heat cause things to expand, making them less dense. You could just read the other answers as well, but here is a neat fact, Water is the only substance know to actually expand when frozen.
2007-04-25 01:04:44 · answer #3 · answered by j train 2 · 0⤊ 0⤋
Denser"cool" fluids "fall"downward by gravitational force displacing the less dense "warmer"fluid thus pushing it up.
2007-04-24 22:32:17 · answer #4 · answered by Rob M 1 · 0⤊ 0⤋