U3AOS2 Topic 2: Gravitational Forces

The Gravitational Force equation shows the force on a mass from each object’s gravitational fields. (Note: this is an action-reaction force)

\[ F = G\frac{M_1M_2}{r^2} \]

Use the simulation below to check your calculations and see the effects of changing variables.

Created with GeoGebra®, by Barb Newitt, Link

The only graph for this section is the Force vs Distance graph which are non-uniform. We have seen in the Work chapter that $ W = Fs $. In this case it is the same thing. Therefore to find GPE, we just use the area under the graph, calculating the area with the same method as we did in the Gravitational Field Strength section. The Work equation then becomes:

\[W = Fs = area under graph \]

To find the area you can count the number of squares that are mostly under the graph. Since here the squares are cut in half you can count every other square. However the next example is more complex than the current one. 

You may need to click the graph and zoom out to see it.

Created with GeoGebra®, by Patrick Dougherty, Link