spread out
As the air in the balloon is heated from the flames, the air becomes lighter. So much lighter than the surrounding air that the balloon eventually rises from the light air in it.
Fire contacting with the air inside the balloon. The heated air within the balloon is less dense than the ambient air surrounding it, therefore for the given volume it is lighter and so rises.
Air expands as it is heated, hence, hot air is less dense than cool air. Hence it rises in a surrounding environment of cooler air.
Flames are the gasses of combustion, heated to the point of glowing. Hot gasses, being less dense and therefore lighter than cold gasses (surrounding air) rise upward until they are redirected by some solid object.
Air heated with a flame, hot air is lighter than cold air and therefore rises above it like something light floating on water
Lighter air will rise; it is the same phenomenon as an air bubble rising in water.
As the air in the balloon is heated from the flames, the air becomes lighter. So much lighter than the surrounding air that the balloon eventually rises from the light air in it.
Cause its lighter than room temperature air..
Fire contacting with the air inside the balloon. The heated air within the balloon is less dense than the ambient air surrounding it, therefore for the given volume it is lighter and so rises.
Generally, its higher temperature. The temperature of a rising magma is generally higher than the temperature of its surrounding rocks. Because of its higher temperature, it is also lighter compared to the surrounding rocks (it has a lower density), so it rises. Imagine a hot air balloon: it rises because the air inside the balloon is heated, heating the air lowers its density (makes it lighter). As long as the density of the air inside the balloon is lower than the density of the air outside the balloon, the balloon rises.
The air warms and expands, becoming lighter than the surrounding air, thus lifting the balloon.
Because the gases filling the balloon are lighter than the surrounding air.
When the air is heated inside the balloon, it expands, causing it to be lighter than the surrounding (and presumably) cooler air. One imagines however, that as the air inside the balloon is heated, some air is forced out (due to expansion), thus resulting in a decrease in the entire apparatus' overall mass (not to mention a decrease in mass due to any fuel's having been used to heat the air in the balloon).
Air expands as it is heated, hence, hot air is less dense than cool air. Hence it rises in a surrounding environment of cooler air.
When air is heated, it expands, it becomes lighter and goes up. Cold air is denser and heavy. That is why it sinks down. When hot air rises, cold air from surrounding area rushes there to fill in the gap. That is how air circulation takes place.
Flames are the gasses of combustion, heated to the point of glowing. Hot gasses, being less dense and therefore lighter than cold gasses (surrounding air) rise upward until they are redirected by some solid object.
Balloons! Gaseous Helium is easily compressed and is stable, (as opposed to Hydrogen). It is lighter than surrounding air.