Would a helium balloon rise in the complete absence of atmospheric pressure?
If you could get a balloon to stay inflated without anything inside it, it would rise even faster than a balloon of the same volume with helium in it. For a helium balloon to rise, the total weight of all the air displaced must be greater than the weight of the balloon plus the weight of the helium inside it.
What force causes a balloon to rise?
Friction occurs between the moving balloon and the molecules of air it hits as it rises. Both drag and the force of gravity pulling on the mass of the balloon act in a downward force in opposition to the lift. If the lift is greater than the drag and force of gravity, then the balloon rises.
What causes air to leave a balloon?
Air molecules are able to slowly diffuse, or escape, via the surface of the balloon, or tiny holes in the know you tied to keep the darn thing closed. The air pressure is higher on the inside of the balloon (because of the surface of the balloon desperately holding all that air in one place).
What happens to air pressure in a balloon when it floats into the sky?
As the balloon rises, the gas inside the balloon expands because the atmospheric pressure surrounding the balloon drops. The atmosphere is 100 to 200 times less dense at the float altitudes than on the ground. A balloon that is fully inflated on the ground will also have way too much lifting force.
How does pressure affect a hot air balloon?
The molecules that are moving faster hit the walls of the balloons more often, and at a greater force. This means that it takes less hot air molecules to equal the same air pressure of cooler air molecules. The hotter, less dense air inside the balloon help it rise against the cooler, denser atmospheric air.
What happens to a balloon placed in hot water?
put the bottle with the balloon on it into the jar of hot water, and watch what happens. What’s going on: When you put the bottle with the balloon into the first jar, the hot water heats up the air in the bottle and makes it expand. Cool air hasn’t got as much energy, so it shrinks – and the balloon shrinks with it.
Can balloons melt?
When a balloon filled with air is held over a flame, the balloon melts a little bit. When the balloon is filled with water, the water absorbs the heat. This stops the balloon from melting. Because there is no weak point, the balloon doesn’t pop.
Why did the balloon contract and then expand again?
Air is a mixure of gases including oxygen and nitrogen. When the frozen balloon containing unfrozen air is placed into something or onto a surface that is hotter than the boiling point of the liquid air, the mixture of air molecules return back to the gas state and the balloon expands out with the air’s pressure again.
What happens to a film of bubble solution when the air inside a bottle is warmed and cooled?
Explain that heating the air inside the bottle makes the molecules move faster. These molecules push against the inside of the bubble film harder than the surrounding air pushes from the outside. This pushes the bubble film up and out, forming a bubble. Note: Cooling the gas makes the molecules move more slowly.
What happens to the particles in matter when temperature is increased?
With an increase in temperature, the particles move faster as they gain kinetic energy, resulting in increased collision rates and an increased rate of diffusion. With an increase in temperature, the particles gain kinetic energy and vibrate faster and more strongly.