Cavendish - Finding the Mass of the World

Newton knew

but Cavendish found a contstant called the gravitational constant which allowed us to write an equation.

In this equation: F = The force of gravity
G = The universal gravitation constant
m = The mass of the smaller object
M = The mass of the larger object
r = The distance between the centers of the two objects


How did Cavendish find G? Click Here to see a simulation of the experiment

How did this allow him to find the Mass of the world? Well do you know your own weight? This allows you to find your mass if you convert pounds to kilograms. The distance from the surface of the earth to the center of the earth has been known for over two thousand years. (click here to find out how this number was known) Plug those values into the equation and solve.

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