when you go skydiving, of course there are physics involved. upon jumping out of the plane, gravity starts pulling you down with an acceleration of 9m/s^2. if you are smart and want to survive this event then you would most likely have a parachute with you. when you pull the cord, the parachute opens which causes you to slow down. the reason it does this is because it increases your surface area which creates alot more drag/air resistance. so if you are going to go skydiving, make sure you have your parachute because physics says so.