# The mass of planet Earth divided by it's radius=it's gravity?

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Do I understand that right: In next video it says:

The mass of  planet Earth divided by it's radius=it's gravity?

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Video link removed by moderator

Edited by Phi for All
Rule 2.7

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If that's what it says, it's wrong. (trivially so; if we assume "it's gravity" refers to the gravitational acceleration, we can see M/r does not have the units of acceleration. Doesn't have units of force, either, so the two likely suspects are eliminated)

The gravitational acceleration of the earth is g = GM/r^2

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Not going to watch a 6 minute video to look for where he says that.

As swansont points out, there is no such thing as 'the gravity'.  It needs to be more specific.

The gravitational potential above the surface of some mass is -GM/r, which is proportional to M/r, so perhaps by 'the gravity' he means gravitational potential.

It can be expressed in the same units as velocity.

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