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# gravitational field strength

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1. So gravitational field strength is defined as the force exerted per unit mass at a point in the field. So g=F/M so then in my textbook it then goes onto say that it's independent of the test mass used, but how can this be? from the equation surley a leager test mass means a smaller g field so it's dependent?
2. bree crazy gravitons with infinite range cause they have no mass but are affected by mass you get me ?
3. (Original post by Emissionspectra)
So gravitational field strength is defined as the force exerted per unit mass at a point in the field. So g=F/M so then in my textbook it then goes onto say that it's independent of the test mass used, but how can this be? from the equation surley a leager test mass means a smaller g field so it's dependent?
doesn't the M in g=F/M represent the Mass of the thing creating the gravitational force though, eg M would be the earth then a larger test mass wont affect it
4. (Original post by Benniboi1)
doesn't the M in g=F/M represent the Mass of the thing creating the gravitational force though, eg M would be the earth then a larger test mass wont affect it
thinking about it i think its becuase Force has mass in its units so the m's cancel out.
5. Grav force on a mass is prop to the mass.

F=GMm/r^2

g = F/m
6. It's independent because the "F" in your equation is the gravitational force on the mass (which is proportional to the smaller mass in the field) and so the two masses cancel.

, where m is the mass in the gravitational field

, where M is the mass causing the gravitational field and m is the mass in the gravitational field.

Combining these two, we get , and so both the lowercase ms cancel out, giving . From this we can see that g is proportional only to the mass causing the field and the square of the distance from that mass; it is not proportional to the mass experiencing the field.

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