>> So if a simulator shows a deviation from this constant sum, there's something wrong with the simulator and/or the underlying mathematics.
> Not necessarily so
But the "constant sum" I refer to is the sum of gravitational potential energy and kinetic energy in the system. If that were not true, if the sum were not a constant (and remembering this is an ideal model without friction), then energy would not be conserved. So, yes, necessarily so.
> Not necessarily so
But the "constant sum" I refer to is the sum of gravitational potential energy and kinetic energy in the system. If that were not true, if the sum were not a constant (and remembering this is an ideal model without friction), then energy would not be conserved. So, yes, necessarily so.