Purpose:
The purpose of this activity is to investigate the
variables which effect the gravitational force between two
objects and to investigate the effect of gravitational force
upon the motion characteristics of an orbiting
satellite.
Procedure:
1. An object and the Earth are shown in the simulation
window. Click and drag the object to various positions about
the earth and observe the gravitational force vector. In the
diagram below, draw a force vector (arrow with arrowhead) to
depict the direction and relative magnitude of the force
acting between the earth and the object. Note: the size of
the arrow is indicative of the strength of the force.
2. Is the effect between gravitational force and distance
of separation (between object and Earth) an inverse or
direct effect? ______________
3. Click and drag the object to various
distances from the center of the Earth in order to
determine the effect of distance upon the
gravitational force. Examine the effect of
doubling, tripling and quadrupling the distance of
separation (as measured from Earth's center).
Consider the earth's surface to be a distance of
one Earthradius (1 R_{Earth}). Use the
table at the right to record data for wholenumber
multiples of R_{Earth}.
4. Return the object to a distance of
approximately 35 Earth radii from the Earth's
center. Now alter the mass of the object and the
mass of the Earth. What effect  direct or inverse
 do each of these alterations have upon the
gravitational force between the object and the
Earth?

Distance

F_{grav}
(N)

1•R_{Earth}


2•R_{Earth}


3•R_{Earth}


4•R_{Earth}


5•R_{Earth}


6•R_{Earth}


7•R_{Earth}


8•R_{Earth}


9•R_{Earth}


10•R_{Earth}


5. Use the simulation program to answer the following
questions:
If the separation distance between the object
and the Earth is ... (see step #3)
... increased by a factor of 2, then the Fgrav is
___________ by a factor of _____.
... increased by a factor of 3, then the Fgrav is
___________ by a factor of _____.
... increased by a factor of 4, then the Fgrav is
___________ by a factor of _____.
If the mass of the object is ... (see step #4)
... increased by a factor of 2, then the Fgrav is
increased by a factor of _____.
... increased by a factor of 3, then the Fgrav is
___________ by a factor of _____.
... decreased by a factor of 4, then the Fgrav is
___________ by a factor of _____.
If the mass of the Earth is ... (see step #4)
... increased by a factor of 2, then the Fgrav is
increased by a factor of _____.
... increased by a factor of 3, then the Fgrav is
___________ by a factor of _____.
... decreased by a factor of 4, then the Fgrav is
___________ by a factor of _____.
Summary Statement:
Summarize your findings from this lab.
Do the Gravitation
Activity.
