Hi, I got 2 questions concerning Centripetal force. I am thankful for every answer I get ! 1) Let's say a car is driving very fast in a loop with radius r on Earth where air resistance and friction doesn't exist. Let's say the car's engine stops and when the car gets to the top of the loop with unacceptable velocity v so that g>(v^2)/r. This will mean that the normal force stops existing and that gravity will make the car fall. But.. why? As long as v is big enough the gravity and normal force will provide the car with centripetal force.. I realize due to common sense that the car will fall but I simply can't wrap my head around and answer why it'll fall.. other than simply saying the centripetal acceleration is smaller than g...... 2) Let's say the Earth's spinning velocity v increases to a speed so that (v^2)/r=0.5g This means that the measured gravity on earth would decrease by half... Again I can't really prove exactly why this happens.. I try to picture it in my head that in this instance half of the gravitational force G is "used up" trying to keep people from flying away from Earth.. Is this correct? Can you tell me a more correct way of picturing this if not?