00:01
In this problem, we're going to talk about the gravitational field.
00:03
So consider that we have a massive object that has a mass capital m, and we want to know what's the gravitational field that's generated by this mass at a distance r from the center of the object.
00:19
This distance here is r.
00:22
So the gravitational field, we usually call it lowercase g, is equal to newton's gravitational constant.
00:30
G times the mass m divided by r squared.
00:36
Notice that the gravitational force that acts on a body that has a mass m and little m and is located at a distance r from the other body is equal to the gravitational field times m.
00:51
Particularly the gravitational field is also the gravitational acceleration of a free body at that point.
01:09
So for the earth, the gravitational field or the gravitational acceleration is equal to 9 .8 newtons per kilogram or it could also be written as meters per second squared.
01:22
Either one is fine.
01:26
And this is the gravitational field at the surface of the earth.
01:36
This is a gravitational field at the surface of the earth.
01:41
Okay? so this means that here we have the earth...