Gravity is not the only force. Other forms of force exist. Multiple forces can affect an object at the same time. Forces can counteract gravity, making an object move against the direction of gravity. These cases do not disprove gravity.
Objects can move against the direction of gravity, and flat-Earthers use it as “evidence” that gravity does not exist. In reality, there is at least a force other than gravity affecting the object, in the opposite direction from gravity, with a larger magnitude. Continue reading “Countering Gravity”
Buoyancy is an upward force exerted by a fluid (liquid or gas) that opposes the weight of an immersed object. Buoyancy happens because the fluid has a pressure gradient. Pressure gradient occurs because the fluid is affected by acceleration, such as the Earth’s gravitational acceleration.
Flat-Earthers makes buoyancy as an “explanations” on how things fall. They are wrong. Without Earth’s gravitational acceleration, buoyancy will not occur.
Continue reading “Buoyancy”
A hot air balloon rises because it has buoyancy. Buoyancy is the upward force that is exerted on the trapped hot air because its density is lower than the surrounding air. If buoyancy is greater than the force of gravity — or the weight of the balloon—, then the balloon will rise.
The basic physics escape most flat-Earthers. To them, the fact that a hot-air balloon rises is an ‘evidence’ that gravity does not exist. They believe things go up or down because of density. They are wrong.
Continue reading “Hot Air Balloon and the Force of Gravity”