Introductory Physics - Finding "little g"

  • #1
OP warned about not using the homework template
Hello i am new,

I have written this piece for homework with reference, and wondering how i can write it better.
Maybe i have written too much or too little, i would appreciate some help.

Regards.

Little g


Little g, what is considered as G-Force or Gravitational Force is the force in which Gravity itself has effect on, for example we as people are subjected to G-Force, a car accelerates produces G-Force, as it will break suddenly or decelerate, or turn sharply this is also under G-Force conditions.

It seems that our planet has a Gravitational Force in which we can observe and in fact, almost all physical objects are subject to it its own G-Force, but it is the Earths Gravitational Force which overpowers them all.

Gravitational Force attracts object of Mass towards each other, it is G-Force that causes the acceleration of these physical objects, an object on incline plane will fall due to gravity, the movement of the object is because of Gravitational Force.

So little g stands for the amount of Acceleration cause by Gravity, also referred to as G-Force (Gravitational Force) and the big G is Newton’s [1] Gravitational Constant. The Newtonian Constant of Gravitation is used to calculate the attractive force of gravity between objects. Big is G is still only a known value to 3 significant figures.

The gravitational constant Big G, little g, the acceleration due to earths gravity. The little g value is dependent upon the location as the earth’s surface has slight variations. These varying from density of geologic structures , this also means that the earth may not be perfectly spherical, in that the earths surface is further from its center at the equator than it is at the poles.




[ref] PHYS.ORG
 

Answers and Replies

  • #2
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You seem to be using the term G-force inappropriately and frequently. You would probably be much better off if you deleted every instance of the phrase G-force.

- Matter has a property we call mass.
- All matter is attracted to all other matter by a force we call gravity.
- The force of gravity is proportional to the mass of the objects and inversely proportional to the square of the distance between them
- The proportionality constant, i.e. the scale of the gravitational force is called the gravitational constant which we denote as G
- All of the above statements are summarized as an equation F = (G m1 m2)/R^2 which we call Newton’s law of gravitation.
- The force of gravity is comparatively weak, and generally the force is only significant if at least one of the two bodies is very massive
- Here on the surface of the earth the most significant gravitational force we experience every day is the attraction of objects to the very massive earth.
- On the surface of the earth, from the lowest valley to the highest mountain the distance from the center of the earth varies by less than 0.15%. A typical value is called the radius of the earth.
- With Me as the mass of the earth and Re as the radius of the earth, the gravitational attraction of an object of mass m to the earth is F = (G Me m) / Re^2
- Since the mass of the earth is fixed and the distance is very nearly fixed at Re, we can combine all of these constants and write the force of gravity on the surface of the earth as
F = m g where g = G Me / Re^2
- m g is often called weight
- g has units of acceleration and is called the acceleration due to gravity.
- Other forces we experience are also proportional to mass in particular the centripetal acceleration we experience when moving in a curve or the linear acceleration experienced riding a rocket. Because these are proprtional to mass, we compare them to gravitational force basically using the gravitational force as a unit to quantify other accelerations. We confusingly call this unit G-forces. They have nothing to do with gravity.
 
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  • #3
BvU
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Hello Max, :welcome:

Well, that was a hefty response to your first posting, wasn't it ? It leaves me wondering whether that really was the kind of help you expected ... :rolleyes:

Cutter's reply is totally correct physics, but my estimate is that you are just getting started in physics and haven't really treated the big G in class yet -- perhaps you found it by googling and wanted to compose a nice essay around the G & g.

Can you help us helpers and tell us a little more about your circumstances, like where you are in your curriculum, whether I completely mis-guessed (I'm known for my total lack of telepathic capabilities) and so on ?

##\mathstrut##
 
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  • #4
nrqed
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Hello i am new,

I have written this piece for homework with reference, and wondering how i can write it better.
Maybe i have written too much or too little, i would appreciate some help.

Regards.

Little g


Little g, what is considered as G-Force or Gravitational Force is the force in which Gravity itself has effect on, for example we as people are subjected to G-Force, a car accelerates produces G-Force, as it will break suddenly or decelerate, or turn sharply this is also under G-Force conditions.



[ref] PHYS.ORG
There seems to be several misconceptions in this sentence. First of all, "little g" is not a force. It is the acceleration that an object experiences near the surface of the Earth when only gravity is acting. The actual force the object experiences is mg, its mass times g. Also, you seem to be confusing "G forces" with the force of gravity, these are completely different things. When a car accelerates or decelerates, people talk about "G forces" but it has absolutely nothing to do with gravity. These are forces that are due to being in non inertial frames. The terminology might give the impression that is connected to gravity but it is not (it is called this way only because people like to compare the magnitude of a force to the value of mg, which we are used to experience).
 
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  • #5
Hello Max, :welcome:

Well, that was a hefty response to your first posting, wasn't it ? It leaves me wondering whether that really was the kind of help you expected ... :rolleyes:

Cutter's reply is totally correct physics, but my estimate is that you are just getting started in physics and haven't really treated the big G in class yet -- perhaps you found it by googling and wanted to compose a nice essay around the G & g.

Can you help us helpers and tell us a little more about your circumstances, like where you are in your curriculum, whether I completely mis-guessed (I'm known for my total lack of telepathic capabilities) and so on ?

##\mathstrut##
yes you are correct, please excuse me, for being so naive, and my use of terminology.
i have been soo many years outside of full time study and i am now a returning student.

i only just started to use this website,
i really like how it works and hope i will get a better understanding of topics,
and theories of understanding, so any and all feedback is welcome.

sure, this topic is really early in Physics, simplified,
but i will progress into deeper into more theoretical Physics as the year progresses.

I already have gone over things like "how an airfoil generates lift",
"what will cause the stall", and stall prevention, with "little g", i was misguided,
but i believe ill have a better piece to show by the end of the day.

thank you, for you help,
i hope to post something more challenging in future.

regards
 
  • #6
CWatters
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....it is the Earths Gravitational Force which overpowers them all.
Only on Sunday mornings :-)
 
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