Where does Gravitation equals zero?

  • Thread starter Thread starter Sapphiretwirl
  • Start date Start date
  • Tags Tags
    Gravitation Zero
Click For Summary

Homework Help Overview

The discussion revolves around the concept of gravitational forces between two masses, specifically a 1kg mass and a 2kg mass placed 10m apart. The original poster seeks to determine the position of a third mass where the gravitational forces from the two masses cancel each other out, resulting in zero net gravitational force.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the gravitational force formula and its application to find the point where the net force is zero. There are attempts to define distances and forces acting on the third mass, with some participants questioning the relevance of certain variables in their calculations.

Discussion Status

The discussion includes various attempts to calculate the distance from the 1kg mass where the gravitational forces balance. Some participants express uncertainty about their calculations and seek clarification on the steps involved. Guidance has been offered to follow a structured approach to solving the problem, though no consensus on a solution has been reached.

Contextual Notes

Participants are working under the constraints of a homework assignment, which may limit the information they can use or the methods they can apply. There is an emphasis on following specific problem-solving techniques suggested by other members.

Sapphiretwirl
Messages
6
Reaction score
0

Homework Statement



So a 1kg mass and a 2kg mass are placed 10m away from each other, somewhere in between them the force of gravity cancles out. Where would am object with a mass of m be placed so that it is not affected by either of the 1kg and 2kg masses?

Homework Equations



Not sure, something with gravitation,rotational motion, angular velocity Ect.

The Attempt at a Solution



F=G*m1(m)/r
 
Physics news on Phys.org
Your formula is not quite right; see: Gravity

All you need to worry about is the force of gravity. Hint: Will the ƩF = 0 point will be closer to the 1 kg mass or the 2 kg mass?
 
The 1 kg mass of course, but I don't know where to go from there :(
 
Sapphiretwirl said:
The 1 kg mass of course, but I don't know where to go from there :(
Good!

Call the distance to the 1 kg mass "x". What is the force of gravity from the 1 kg mass at that point?

If the distance to the 1 kg mass is x, what would be the distance to the 2 kg mass? What is the gravitational force from the 2 kg mass at that point?

Solve for the distance that makes the net force zero.
 
I've tried but I can't solve for the distance, the furthest I've gotten is this

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

0=6.67*10^-11(2/x^2)
 
Isn't it a bit weird that your formula for the force of gravity doesn't involve the mass m of the object we are looking at?

There are two sources of gravity, each of them acts on the object in a different direction.
 
I got 1.7 meters for x
 
I probably did something wrong
 
Sapphiretwirl said:
I got 1.7 meters for x
Pls post your working, not just the numeric answer. Preferably, do all the working in symbols, only plugging in numbers at the end. Follow Doc Al's recipe.
 
  • #10
I really don't know what I did
 
  • #11
Sapphiretwirl said:
I really don't know what I did
Then start again, following Doc Al's recipe. Answer each question in turn, as far as you can:
Call the distance to the 1 kg mass "x". What is the force of gravity from the 1 kg mass at that point?

If the distance to the 1 kg mass is x, what would be the distance to the 2 kg mass?

What is the gravitational force from the 2 kg mass at that point?
 

Similar threads

  • · Replies 7 ·
Replies
7
Views
1K
  • · Replies 5 ·
Replies
5
Views
3K
Replies
2
Views
2K
  • · Replies 6 ·
Replies
6
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 17 ·
Replies
17
Views
2K
  • · Replies 23 ·
Replies
23
Views
5K
Replies
10
Views
4K
Replies
21
Views
3K
  • · Replies 6 ·
Replies
6
Views
2K