Understanding Newton's Law of Universal Gravitation

AI Thread Summary
The discussion focuses on calculating the gravitational force acting on Earth due to the Sun using Newton's Law of Universal Gravitation. The relevant formula is Fg = G(m1m2 / r^2), where G is the gravitational constant, m1 is the mass of the Sun, m2 is the mass of the Earth, and r is the distance between their centers. Participants clarify that the gravitational constant is G = 6.67 x 10^-11 N m^2/kg^2, and the masses are 1.99 x 10^30 kg for the Sun and 5.98 x 10^24 kg for the Earth. The final calculation yields a gravitational force of approximately 3.39 x 10^22 N acting on Earth from the Sun. Understanding these values and the formula is essential for accurately determining gravitational interactions.
Ecterine
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"Consider the Earth following its nearly circular orbit about the sun. The Earth has a mass mearth=5.98x10^24kg and the sun has mass msu=1.99x10^30kg. They are separated, center to center, by r=93 million miles = 150 million km."

What is the size of the gravitational force acting on the Earth due to the sun?

I'm still setting up the problem...

I think I use the equation Fg=G(m1m2 / r2).

r is the distance between the centers of the two objects.
G is the gravitational constant (so I just leave that as G, right?)

But, is the sun or the Earth m1?
 
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Wait... I just realized how stupid of a question that is. Why do I do this when I'm so tired?
 
K, so now for a better question!

Fg=G(5.98x10^24kg x 1.99x10^30kg / 150,000,000 km)
Fg=G(7.933 x 10^46)Am I on the right track? What do I do with the G?

I know that the gravitational constant G has a value G=6.67x10^-11 N x m2/kg2

If I plug the mass of the sun in as m2 it is...

G=6.67x10^-11 N x 1.99x10^30kg/kg2

but... now I'm lost. :(
 
Fg=(6.67x10^-11 N x 1.99x10^30kg / kg2) (7.933 x 10^46)

:(
 
Ecterine said:
"Consider the Earth following its nearly circular orbit about the sun. The Earth has a mass mearth=5.98x10^24kg and the sun has mass msu=1.99x10^30kg. They are separated, center to center, by r=93 million miles = 150 million km."

What is the size of the gravitational force acting on the Earth due to the sun?

I'm still setting up the problem...

I think I use the equation Fg=G(m1m2 / r2).

r is the distance between the centers of the two objects.
G is the gravitational constant (so I just leave that as G, right?)

But, is the sun or the Earth m1?


The formula for gravitation is F=GMm/R^2. Some people may prefer to rewrite it as F=GM1M2/R^2. Just need to take note that M1 or M is the primary mass and M2 or m is the secondary mass. In this question, the mass of Sun is taken to be M1 or M.

Data used:
Gravitational constant = 6.67x 10^-11 Nm^2kg^-2 = G
Mass of Sun = 1.99x 10^30 kg = M
Mass of Earth = 6.02x 10^24kg = m
Distance between Sun and Earth = 1.5x 10^11m = R

Force acting on Earth by Sun = GMm/R^2
= 3.39X 10^22 N
 
Thank you! :)
 

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