John, MENTOR
Adult, Greece
6 points (HYDROGEN)
July 29, 2009 06:02

A paradox perhaps?

Well, lets assume a person falling from an empty room. Before he touches the ground reaches his finger and touches the ceiling. The gravity force is given by the equation F= G * (m1 * m2)/ r^2. In this case, r=0 hence F should be +00 (positively infinite). That means that the person sould stick to the ceiling because the force of gravity is les (r is greater than zero).

As a matter of fact, I just thought that the equations given in school books might not be precice. For instance what would happen if a proton and an electron get together? The electrostatic force is given by the equation F= k * |q1 * q2| / r^2 ...
TAGS:
imdefined, MEMBER
18, Singapore
4 points (HYDROGEN)
October 9, 2009 08:46

The tips of your fingers will be touching the ceiling, but your whole body is not. If you integrate the gravitational force over your whole body, you find that your acceleration upwards is less.

 		 
 
  
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The tips of your fingers will be touching the ceiling, but your whole body is not. If you integrate the gravitational force over your whole body, you find that your acceleration upwards is less.


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