Gravitational potential?

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#1
So gravitational potential generally is just the potential energy per kg at a point in a field, so it is purely a location-dependent quantity.

As you increase the distance from Earth's centre surely the gravitational potential would increase because more work is required to move it away from the the gravitational pull? The equation is given as

V= -(Gm)/r

so according to this, increasing the distance from Earth's centre means that the potential will decrease? Though i don't see how this makes sense?

Also gravitational potential is defined as being zero at infinity, i know this is partly due to the fact that the g. force approaches zero at infinity but wouldn't the potential be zero at the centre of the Earth since no work is done to move it away from its equilibrium point?

Help is appreciated, pls im bad at physics
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3 years ago
#2
Do you see the negative?

What happens if you go from -2 to -1: it increases.
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3 years ago
#3
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#4
(Original post by tobq)
Do you see the negative?

What happens if you go from -2 to -1: it increases.
Oh, fair enough. Is this due to convention then instead of having the centre of the Earth at zero potential, for which the gravitational potential would be positive?
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3 years ago
#5
Potential is the amount of work, needed, to move something from "a point of infinity" (a point infinitely far away - the edge of the field) to a point, in a field -- REMEMBER THIS!

Gravitation potential is a measure of the amount of work done (energy) needed per unit of mass (kg) to move from a point of infinity, to a point of distance R, away from an object's centre.

The MAGNITUDE will decrease, as R increases, but the VALUE will increase, because as I said, -2 is smaller than -1.

I've also found this confusing before.
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#6
(Original post by tobq)
Potential is the amount of work, needed, to move something from "a point of infinity" (a point infinitely far away - the edge of the field) to a point, in a field -- REMEMBER THIS!

Gravitation potential is a measure of the amount of work done (energy) needed per unit of mass (kg) to move from a point of infinity, to a point of distance R, away from an object's centre.

The MAGNITUDE will decrease, as R increases, but the VALUE will increase, because as I said, -2 is smaller than -1.

I've also found this confusing before.
okay that makes sense, thanks!
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