That's it ! That's all you need to do.
The formula for gravitational potential energy is
PE = (mass) x (gravity) x (height) .
-- Where it says 'mass', write the mass of the object.
-- Where it says 'gravity', write the acceleration of gravity
on the planet where you are. On Earth, it's 9.8 m/s².
-- Where it says 'height', write the height of the object above
the floor, or above the ground, or the roof ... whatever.
When you put those numbers in and do the multiplication,
the answer you GET is the object's PE.
The neatest part is: If you put in the numbers with SI units ...
mass in kg, gravity in m/s², and height in meters ... then you
don't need any more numbers, like constants or conversion
factors etc. The SI units all work together, so that the answer to
the multiplication of those 3 numbers IS the PE with units of joules !
