HP 50G, User Manual, Page: 229 / 887

Page 6-23
Example 4 – Universal gravitation
Newton’s law of universal gravitation indicates that the magnitude of the
attractive force between two bodies of masses
m
1
and m
2
separated by a
distance r is given by the equation
Here, G is the universal gravitational constant, whose value can be obtained
through the use of the function CONST in the calculator by using:
We can solve for any term in the equation (except G) by entering the equation
as:
This equation is then stored in EQ:
Launching the numerical solver for this equation results in an input form
containing input fields for F, G, m1, m2, and r.
Let’s solve this problem using units with the following values for the known
variables m1 = 1.0
×
10
6
kg, m2 = 1.0
×
10
12
kg, r = 1.0
×
10
11
m. Also, enter
a value of 0_N in field F to ensure the proper solution using units in the
calculator:
.
2
2 1
r
M M
G F
⋅
⋅ =