Why does a helium-filled balloon float up when it is released?
because helium has a lower density the oxygen- ie the molecules weigh less in helium
The helium density is lower than that of air, not just oxygen, which is just one component of air.
I hope hope this helps a little more. Thanks for asking.
A helium-filled balloon floats up when it is released because of the principle of buoyancy. Buoyancy is the upward force exerted on an object submerged or floating in a fluid, such as air or water.
To understand why a helium-filled balloon floats, we need to know a little bit about density. Density is the mass of an object per unit volume. If an object is less dense than the fluid it is in, it will float. If it is denser, it will sink.
Helium gas is less dense than the air around us. When the balloon is inflated with helium, the gas inside the balloon is less dense than the surrounding air, causing it to be buoyant. The balloon rises because the buoyant force exerted on it by the surrounding air is greater than its own weight.
To get a more accurate answer, you can perform a simple experiment. Take an empty balloon and a balloon filled with helium. In the case of the filled balloon, the weight of the balloon material itself is essentially the same, but with the helium inside, the overall density of the balloon becomes less than the surrounding air. This difference in density causes the buoyant force to be greater than the weight of the balloon, making it float upwards.
So, the reason a helium-filled balloon floats up when released is that the helium inside is less dense than the surrounding air, creating a buoyant force greater than its weight, causing it to rise.