If ghosts can walk through walls and glide down stairs, why don’t they fall through the floor?

ghosts float, because they cannot stand on anything made of any type of substance

explanation:

ghosts ca pass through objects at will but you will never see a ghost standing on anything

if the forces acting on an object are unbalanced, the object will accelerate in the direction of the net force on the object.

explanation:

this is best explained by having an understanding of newton's second law, which states that f=ma. you see, when the forces are unbalanced, net force (sum of all forces) is not zero. therefore making it necessary for the object to have an acceleration in the direction of the net force.

gas and liquid