- As a satellite enters into orbit, its kinetic and potential energy is increased right? if so, how is energy conserved - can someone correct me if I am wrong and me work this out
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I'd think of forces as internal/external for this and by that same idea work:
if an object is acted upon by a force that is "internal" (within the system) e.g gravity, then the total energy of that internal system will remain constant as the work done by these forces transforms energy to one type to another.
If the object is acted upon by a force that is "external" (not part of the system e.g Thrust force, then the total energy of a system is changed as the external forces do work on the system itself rather than transform energy.
I think of systems like a jug, internal forces change the amount of one fluid in a jug but retain the volume of the overall fluids combined however external forces change the overall volume of fluids in the jug. (Could be bad but works for me)
So in this context, the force applied to get the satellite into orbit from stationary is the external force and hence external work is done on the system; and this adds energy into the system and therefore the mechanical energy (U + KE) increases.
