Re: gravity and rotation

Dear Morgan.



Sorry for the delay.

First we need to clear up definitions. Using "g" to denote force is 

not entirely correct, although I am guilty of it myself sometimes. "g" 

is the symbol we use to indicate the acceleration of gravity at the 

surface of the earth. Usually this is taken to be 9.8 m/s^2 downward. 

The force of gravity is the mass of an object times the acceleration 

of gravity, this is what we call weight. In a rotating body, in space 

for example, we can simulate the gravity at the earth's surface by rotating 

the object. The formula for this is the centripital acceleration formula.

Centripital acceleration is equal to the velocity squared divided by the

radius. This formula can be found in any high school physics text book. 

  The second part of your question is a little more complicated. It 

will require trig. The total force acting on the bug will be an addition 

of the forces. The easiest way to picture this is to draw a picture of 

the bug. Now draw arrows pointing in the direction of the forces, one to 

the right and at the end of this draw one down. If you now connect the 

tail end of the first arrow with the head of the second arrow, it should 

look like a right triangle. This is called vector addition. The hypotenuese 

of the right triangle is the resultant force experienced by the bug. If the 

arrow down is very large compared to the arrow to the right, the bug feels a 

more downward force. If the arrow to the right is much bigger, as it would 

be with a higher speed of rotation, the bug feels a more outward force. 

This is very simplified but I think you can get the idea.