What for upposes the force of gravity?

Answer 1

Any force directed away from the center of the Earth does that.

Examples include:

-- the buoyant force on an object in water

-- the buoyant force on a helium party balloon

-- the buoyant force on a battleship

-- the lift force on the wings of an airplane in level flight

-- the tension in the stem of an apple hanging from the tree

-- the force of arm muscles when you lift a cup of coffee

-- the force of leg muscles when you climb a step.