# Find the gravitational force between then sun and the earth

## 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. :/

Chestermiller
Mentor
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

SteamKing
Staff Emeritus
Homework Helper

## 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?

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?