a. the cool outside air pushes the balloon higher?
b. the temperature difference between the inside and outside air causes convection currents
c. hot air has a lower density than cold air
d. cooler air diffuses more slowly than the warmer air
Please explain this to me... Thank you!
2007-02-17 08:05:46 · 4 answers · asked by laweezer08 1 in Science & Mathematics ➔ Chemistry
a and c are both correct. a because c.
Think of the cold air as water and the hot air as... i dunno, a beach ball. If you push the ball down into the water, it will push water out of its way, but the water will "want" (because of its weight or density) to fill the place taken up by the ball. Accordingly, if you let go of the ball, it will be pushed up and out of the water. The situation is the same for the hot air ballon in colder air.
2007-02-17 08:14:26 · answer #1 · answered by cato___ 7 · 0⤊ 0⤋
C - see ? ( the first explanation should suffice )
you might want to suggest a better text to your teacher - i was a bit of a problem in school and would have made a good argument that A. is also correct ( in fact MOST correct due to the forces involved - but trust me they want C. for an answer - don't be a trouble maker ! lol )
the cool outside air - being denser - exerts a force on the outside of the balloon pushing it into air with equal density ( the same way water pushes a scuba diver upwards when he drops his weight belt )
2007-02-17 16:13:27 · answer #2 · answered by Anonymous · 0⤊ 0⤋
C. And as a result, a mass is larger. In other words, 20 lbs of hot air takes up more room than 20 lbs of cold air. So it "floats" on the air much as a ship floats on water.
2007-02-17 16:09:56 · answer #3 · answered by TychaBrahe 7 · 0⤊ 0⤋
Because I have a LARGE house, and the downstairs is always colder than the upstairs, I know that hot air is less dense than cold air, so heat rises. Your correct answer is C.
2007-02-17 16:26:59 · answer #4 · answered by Anonymous · 0⤊ 0⤋