Gravitation Potential Energy help (1 Viewer)

mecramarathon

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I have this stupid Q to do for physics

Q: Would a massive planet have a higher or lower gravitation potential energy compared to Earth?


My reasoning was: it depends because wouldn't a massive planet with a mass of 2m and a radius of 2r still have the same GPE value compared to earth with a mass of m and a radius r?

Is this correct?
 

MrMMMan

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GPE=-GMm/r

r = distance from the planet's centre to particle/object in the field
m= mass of particle/object
M=mass of planet

So for the same mass m and distance r the GPE is proportional to M, the mass of planet. So more 'massive' planet would have 'higher GPE' in this interpretation.
 

raniaaa

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gpe is the work done on an object to bring it to a certain point in a body's gravitational field.

W= Fs

for a greater mass more work would need to be done in order for it to cover the desired distance. therefore the massive planet would have a greater gpe.
 

MrMMMan

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Actually it should be 'lower GPE' due to neg sign. sorry about that
 

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