factors affecting the strength of a gravitational field (1 Viewer)

[~Han~]

i was wondering if anyone can point me in the right direction for websites with information on the factors that affect the gravitational strength of an object...i googled but it didnt come up with anything useful

 

[shinji]

Isn't it just mass and distance between the objects?

yeh ur right.

and at earth, the gravity is stronger around the north & south poles (i thnk) as it is closer to the earths' core, where as the equator is more distant thus having a reduced gravitational pull. ( although it doesn't really vary by much )

 

[~Han~]

wow is that all? haha i thought there'd be more ot it..thanks so much

 

[YBK]

wow is that all? haha i thought there'd be more ot it..thanks so much

i was doing the same dot point a few days ago..

all i wrote down was mass and distance between two objects.

 

[zeropoint]

Keep in mind that as you move around the earth, the local value of g will vary even at constant elevation due to variations in the density of rocks below the earth's crust. Google: gravitational anomaly maps.

 

[~Han~]

thanks so much for your help

 

[92LUCAS]

does anyone know why and how does the density of the earth affects g ?

oh and i dont understand why centripetal force/the axis of the earth affects it either ?

thanks

 

[icecoffee]

The strength of the gravitational force depends on the mass of the two objects and the distance between them [as evident in Newton’s law]. It is also varied due to the Earth’s thickness variation in the crust, centrifugal effect of spinning…

Earth’s crust is variable in thickness: The thicker the crust, the greater the value of g.
Earth is not a perfect sphere: Value of g is greater at the poles since they are closer to the centre of the earth. (flatter at poles)
Earth is spinning: As the earth is spinning, we are ‘flung’ further away and therefore the value of g is less.
Earth’s surface is not flat – it has mountains, oceans, trenches… : If you are standing on a mountain, you are further away from the core and the value of g is less.

It's rather trivial and i'm not even sure if it's right but it's what i had in my notes.

 

[92LUCAS]

do you think its because there is, in a sense, more 'mass' when its more dense ? so this makes M(earth) larger ? LMAO just a thought ....

 

[tELLEvision]

does anyone know why and how does the density of the earth affects g ?

oh and i dont understand why centripetal force/the axis of the earth affects it either ?

thanks

we did a prac on this. = ]

using the mathematical equations

F (gravity) = (G x M x m ) divided by d squared

and

F (gravity) = m x g


where G = universal gravitational constant
M = the mass of the earth
m = the mass of the object
d = distance between the centre of the objects.
g = acceleration due to gracity

solve simultaneously,

g = (G x M) divided by d squared.

1. due to the earth being a flattened sphere, g is slightly larger and the poles than at the equator ( distance decreases, g increases)

2. altitude has slight effect ( distance increases, g decreases)

3. due to the varying densities in the lithosphere g can also vary ( mass increases, g increases)

4. due to the earths spins and the centrifugal force, g is smaller at the equator than at the poles.

 

[Spark_Coaching]

What icecoffee stated is spot on, so apart from The factors we can ascertain from Newton's Law - distance and mass, the other main factors affecting strength of gravitational force are Altitude, Earth being flatter at the poles, Centripetal force and Varying density of the Earth.