Change in GPE and Ek as object approaches a planet

AI Thread Summary
The discussion centers on a misunderstanding of gravitational potential energy (GPE) in relation to distance from a mass. Initially, it was assumed that GPE increases as an object moves away from a planet, but the expected answer indicated that GPE decreases as the rocket approaches the planet. The confusion arose from interpreting the graph, which showed a negative slope, indicating a decrease in GPE. Upon clarification, it was understood that while the magnitude of GPE appears to increase, the negative sign indicates that the energy is actually decreasing. This highlights the importance of correctly interpreting the signs in physics graphs.
Saado
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This is not a homework question.

Whilst looking over at previous exam papers on classical physics, I came across this question in the attachment. I always assumed gravitational potential energy increased as you moved further away from a mass. But the expected answer to this question shows the GPE increasing as the rocket gets closer to the planet. I'm assuming the increase in kinetic energy is due to the field strength of the planet but I can't get my head around why the magnitude of the potential energy is increasing instead of decreasing as the object moves closer to the planet.
 

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The expected answer in the attached thumbnail shows the gravitational potential energy decreasing (slope of curve is negative) as the ship moves from A to D and then remaining constant. Where do you see anything increasing in that curve?
 
Oh I see my problem. I read the graph as the magnitude increasing but realized that's wrong. Thank you.
 
Only the magnitude is increasing; the negative sign before magnitude makes it decreasing.
 
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