Find the gravitational force between then sun and the earth

AI Thread Summary
The discussion focuses on calculating gravitational forces using the formula Fg = (G(m1)(m2))/r^2. For the first problem, participants point out that the mass of the sun is missing from the equation and emphasize the need for proper units in the final answer. In the second problem, confusion arises regarding the placement of the gravitational force value and the need to clarify the units of the gravitational constant G. Participants express the chaotic nature of the calculations and seek assistance to ensure accuracy. Clear communication of units and correct application of the gravitational formula are essential for solving these problems effectively.
Julia Darko
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Homework Statement


1)Find the gravitational force between then sun (2*10^30 kg) and the Earth (5.97*10^24 kg). Earths distance from the sun is 1.5 * 10^11m.

2) find the distance between a 5 kg object and a 10kg object if their gravitational force is 1*10^-4N.

Homework Equations


Fg= (G(m1)(m2))/r^2

The Attempt at a Solution


1) (6.67*10^-11)(5.97*10^24)(10)(5)/(1.5*10^11)^2= 3.50*10^22

2) (6.67*10^-11)(10)(5)(1*10^-4)/r^2=
√3.33*10^-13 = √r^2

So... 5.77*10^-7

Yes... these "answers" may look chaotic which is why I am here for some assistance. :/
 
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In doing question 1, where is the mass of the Earth in the equation? What are the 10 and the 5 doing in the equation?
In doing question 2, the 1*10^-4 should be on the other side of the equation.

Chet
 
Julia Darko said:

Homework Statement


1)Find the gravitational force between then sun (2*10^30 kg) and the Earth (5.97*10^24 kg). Earths distance from the sun is 1.5 * 10^11m.

2) find the distance between a 5 kg object and a 10kg object if their gravitational force is 1*10^-4N.

Homework Equations


Fg= (G(m1)(m2))/r^2

The Attempt at a Solution


1) (6.67*10^-11)(5.97*10^24)(10)(5)/(1.5*10^11)^2= 3.50*10^22

Where is the mass of the sun in the equation above?
Where are the units of your answer?

2) (6.67*10^-11)(10)(5)(1*10^-4)/r^2=
√3.33*10^-13 = √r^2

So... 5.77*10^-7

Yes... these "answers" may look chaotic which is why I am here for some assistance. :/
What is the factor 10-4 for?
What are the units of G?
You need to state the units with your answers, otherwise your calculations are incomplete and ambiguous.
 
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