naa these coin scenarios are nothing more than myths.. a penny or dime dropped of a skyscraper would flutter in the wind, and would have no more impact than if you dropped it off the roof of a 1 story house.. those are scenarios of what would happen if there was no air, and things kept accelerating - but when you have air pressure, things don't happen like that.. even a person jumping off a building will reach a maximum speed and stop accelerating before they hit the ground..