Gravitational force for a ball and particle

AI Thread Summary
To determine how far a 110kg ball must be from a particle for the gravitational pull to equal that of Earth, the gravitational force equation Fg = gMm/r^2 is applied. The mass of the particle is not needed as it cancels out in the calculations. The user initially miscalculated the distance but realized the need to square root the final result. After correcting the calculation, they arrived at a distance of 7.49 x 10^-10 meters, but noted that this answer was marked incorrect. The discussion highlights the importance of careful calculation and understanding the variables involved in gravitational force problems.
PKay
Messages
10
Reaction score
0

Homework Statement


How far from a very small 110kg ball would a particle have to be placed so that the ball pulled on the particle just as hard as the Earth does?


Homework Equations



Fg= gMm/r^2

The Attempt at a Solution


I used the equation and plugged in the numbers for the ball and the earth, but then I realized that I needed to use the mass for the particle. However, I don't know what the mass for the particle is.
 
Physics news on Phys.org
It does not require the mass of the particle.
 
Am I supposed to leave it as a variable?
 
It's your choice..if you do that, you can see it cancels out ultimately.
 
Thanks! I see it now... I end up getting R= R^2 * Mball/Mearth I'm hoping I'm in the right direction.
 
Yes.
 
I get 7.49-10^-10 but it says I'm wrong.
 
Whoops. I'm sorry. I forgot to square root that. Thanks so much for your help! Now to tackle the other 2 monstrous problems.
 

Similar threads

How to get gravitational force on a gaseous particle?
Replies
28
Views
2K
Newton's law of gravitation, energy and centre of mass question
Replies
6
Views
501
Why do I feel centrifugal acceleration when standing on a revolving ball?
Replies
1
Views
1K
(Magnetism) Magnetic pull force on a steel ball
Replies
4
Views
2K
Newton's shell theorem - all mass is concentrated at its centre
Replies
16
Views
1K
What are the forces acting on an object?
Replies
2
Views
1K
Why the large ball falls farther than the smaller one?
Replies
31
Views
4K
How to find the force exerted on a particle on the Earth by the Sun
Replies
1
Views
2K
Calculating distance between charged Balls
Replies
10
Views
2K
Friction force on a ball falling through a body of water
Replies
9
Views
1K

Hot Threads

Recent Insights

Back
Top