wtf?
Quote:
yes, actually
think of it when a helicopter takes off, the propeler exerts a force greater than its weight onto the ground to lift off. and in order to stay flying, must exert the same amount of force as its own weight. otherwise it will drop.
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what type of crazy pyhsics is this?
the ground is not exerting a force on the helicopter. gravity is exerting a force. to lift off the ground, you have to exert a force greater than gravity to take off.
this business about exerting a force to the ground is crap!
think about it in these terms. say 'i exert' 900N to the ground. I want to take off, so by that reasoning, i have to "exerts a force greater than its weight onto the ground to lift off" ,so i go and find another 900N person and hold them up? pfft.