Image a world that superficially appears to have Earth-like gravity. However, the moment you do not in any way touch the ground or something else that is touching the ground, there is no gravity for you. E.g.:
- You jump, you're floating.
- You run (definition= "to go quickly by moving the legs more rapidly than at a walk and in such a manner that for an instant in each step all or both feet are off the ground"), you float.
- You touch a wall or somebody standing/sitting/whatever and then jump, it will be like a jump on Earth.
This is true for everything (animals, stones, houses, water, etc.) except atmosphere (or no one would be able to breathe).
To go back to the ground, you'll have to touch something that is already touching the ground. (And depending on what hight your are, you could easily crash.)
I imagine that transportation could get easier. But behaviour like throwing would not be recommended.
How does this change every day life? (Imagine a 21st century development)
Would keeping the momentum make life more complicated? (E.g. when jumping up, you would keep your momentum - like in vacuum? - and float up)
I was thinking about movement in space with my question about the momentum: E.g. thrusters of an Earth space probe fire in direction A, they move the space probe in opposite direction B with low friction. Thus, a person jumping is like a space probe whose thrusters fired.