LINKS


gravitational attraction  
   
   
inverse square law the attraction between two objects is = G(m1m2)/r2 thererfore...
CHANGES IN THE DISTANCE
double the distance (2 x)...
new force  vs old force

G(m1m2)

------------

(2r)2

 vs

G(m1m2)

-----------

r2

     

1 x G(m1m2)

------------

(2r)x(2r)

vs

1 x G(m1m2)

-----------

1r2

1/4 to 1

and the new force = 1/4 x the old force, or 4 times smaller

triple the distance (3 x)...
new force  vs old force

G(m1m2)

------------

(3r)2

 vs

G(m1m2)

-----------

r2

     

1 x G(m1m2)

------------

(3r)x(3r)

vs

1 x G(m1m2)

-----------

1r2

1/9 to 1

and the new force = 1/9 x the old force, or 9 times smaller

 

   
  quadruple the distance (4 x) and the new force is 16 times smaller
  5x , 25 times smaller and so on.
  halve the distance (.5 x) ...
new force  vs old force

G(m1m2)

------------

(r/2)2

 vs

G(m1m2)

-----------

r2

     

1 x G(m1m2)

------------

(1 x r/2)x(1 x r/2)

vs

1 x G(m1m2)

-----------

1r2

4 to 1

and the new force = 4 times the old force, or 4 times bigger

make the distance 3 times less (1/3 x) ...and the new force = 9 times the old force, or 9 times bigger

make the distance by 4 times less (1/4 x) ...and the new force = 16 times the old force, or 16 times greater

divide distance by 5, force increases by 25 times

 

 

 

  CHANGES TO THE MASSES
  double either one of the masses (2 x)
new force  vs old force

G(2m1m2)

------------

(r)2

 vs

G(m1m2)

-----------

r2

     

G(2m1m2)

------------

1

vs

1 x G(m1m2)

-----------

1r2

2 to 1

and the new force = 2 times the old force

 

double both of the masses
 
new force  vs old force

G(2m12m2)

------------

(r)2

 vs

G(m1m2)

-----------

r2

     

G(2m1 x 2m2)

------------

1 r2

vs

1 x G(m1m2)

-----------

1r2

4 to 1

and the new force = 4 times the old force

  triple either one and the force will be 3 times greater, and so on...

Triple both of the masses and the new force will be 9 times greater

 

The table below is provided for reference, do not try to memorize it. Make one yourself to help understand how to figure a new combination out.

 

 

change what... multiplier m1 m2 r r2 Fnew/Fold
increase
distance
by

and
force
decreases

1 1 1 1 1 1
2 1 1 2 4 1/4
3 1 1 3 9 1/9
4 1 1 4 16 1/16
6 1 1 6 36 1/36
9 1 1 9 81 1/81
10 1 1 10 100

1/100

change what... multiplier m1 m2 r r2 Fnew/Fold  
decrease
(divide)
distance
by __
and
force
increases
by
the
square
1 1 1 1 1/1 1  
2 1 1 1/2 1/4 4  
4 1 1 1/4 1/16 16  
5 1 1 1/5 1/25 25  
6 1 1 1/6 1/36 36  
9 1 1 1/9 1/81 81  
10 1 1 1/10 1/100 100  
change what... multiplier m1 m2 r r2 Fnew/Fold  
change
one
mass
by
____
and the
force
increases
by the
same
factor

 

1 x 1 1 1 1 1  
2 x 2 1 1 1 2  
1 2 1 1 2  
3 x 3 1 1 1 3  
3 1 1 1 3  
4 x  4 1 1   4  
1 4 1 1 4  
5 x 5 1 1 1 5  
10 x 1 10 1 1 10  
change what... multiplier m1 m2 r r2 Fnew/Fold  
change
both
 masses
by ____
and the
force
increases
by the
square
of the factor
2 x 2 2 1 1 4  
3 x 3 3 1 1 9  
4 x 4 4 1 1 16  
5 x 5 5 1 1 25  
6 x 6 6 1 1 36  
9 x 9 9 1 1 81  
10 x 10 10 1 1 100