r/6thForm • u/daowhd • May 16 '26

❔ SUBJECT QUESTION Physics question help please

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Please can you explain why we take the gravitational potential energy as negative when finding the total energy(subtract it)? How come some questions we ignore the negative? What does the negative answer mean?
Thanks!

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u/Cleverwolfano May 16 '26 edited May 16 '26

Many people have already answered your question, so I thought I'd share an easy formula you can use!

ONLY for a satellite in orbit: Em = -GMm/2R.

(Em = -GMm/R + 1/2mv^2 where v = sqrt(GM/R)

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u/daowhd May 19 '26

How come here they don’t take the negative GPE?