Imagine Kiora is sitting on a bench in a park on a calm day, holding a helium-filled balloon on a string. If Kiora suddenly releases the string, what happens to the balloon, and why? Make your response very short.
The helium-filled balloon will ascend into the air after Kiora releases the string. Helium is lighter than air, which makes the balloon buoyant. Since there is no longer anything tethering the balloon to the ground, the buoyant force allows it to rise into the atmosphere.