Gravitational force Definition and 497 Threads

The Cavendish balance measures the gravitational constant G. To do so requires us to know the magnitude of the smaller and larger masses in the apparatus. However, mass is derived from the weight of an object, which is the gravitational force upon an object, which in turn requires the value of...

I am not sure if there is in fact a classical description of how it occurs, but I’d like to know if there isn’t too!

According to some papers I've found [1], [2] expanding voids can be found inside clouds of denser materials that can cause them to eventually collapse. I have a question about this: Overdensities generally expand up to a given turnaround radius and then collapse. However, as the elements in the...

I would like help with an issue that I have not yet fully mastered. Consider a particle resting on a plane, it is subjected to a gravitational force, which can be interpreted as the result of a deformation of space-time. It remains at rest due to the upward binding reaction provided by the...

It is clear that the speed is constant because dark matter hasa gravitational effect on stars, so when a star is further from the core, gravitational force of it is smaller, but the net gravitational force of dark matter is bigger. So the net force acting on each star has to be the same. So...

When you are calculating the gravitational force between two masses and one of them is a black hole, do you still use the distance to the center of mass as you would in Newtonian gravity to find the force? Or is the distance measured only to the event horizon? Is the inverse square law modified...

Suppose there is a very large mountain adjacent to a pendulum such that there is a horizontal component gravitational force of ##10^{-5}g## acting on the otherwise ideal pendulum. How would one use a perturbation to add that effect to first order? My initial thought would be to figure an angle...

Is there a gravitational analog of electromagnetic force? [Apart from the obvious "static" forces, ie electrostatic between fixed charges and gravitational between fixed masses.] I am thinking of the classic situation of a moving charge (or current) creating a magnetic field which then...

I am trying to understand gravity inside an exponential axysymmetric mass disk with no thickness. I know there are exact solutions for this case, such as the Mestel disk or the Kuzmin model, but I want to work out a simpler solution. I am approaching the subject by linear superposition. For a...

why is that the gravitational force proportional to product of masses why not sum of masses or something else .........

Picture below. Both bodies are made of same material but the body placed in water had 2.4 times greater mass. What is the relationship between buoyancy Force and gravitational force between body in water and body in air?I have no clue how to solve this. I know that body with greater mass has 2.4...

I was reading this, but am confused: https://nautil.us/the-remarkable-emptiness-of-existence-256323/

It asked for a snappy title so don’t judge! I’m here for the physics not the BS. And I’ve checked my Dunning-Krugerness & Confirmation Bias at the door! In a way I’ve always been fascinated by physics and the biggest of questions but recently I thought I’d jump in and actually participate as...

I solved that the hollowed out mass is M/8, which is correct. I don't understand why it is incorrect to substitute the remaining mass (7M/8) back into the F = G*m1m2/r to produce the force. Why is the solution the force of the whole lead sphere minus the force of the “hole” lead sphere, which is...

Can gravitational force have influence at objects at infinitely long distance? Is gravitational force in the form quantum packets?

I do understand that gravitational the electromagnetic force between two electrons or protons is very large compared to the gravitational force between them. I can see this by looking at the equation of gravitational force (##F= \frac {Gm_1m_2} {r^2}##) and the equation of electrical force given...

It's been more than 60 years since I attended high school, and I am trying to learn and understand concepts in Newton's physics that were not taught and were not part of the school curriculum during the 1950's. It is my understanding that the current mathematics taught and used in our...

A station is orbiting a planet at a distance R1, a moon is orbiting the planet at distance R2 with the period T. The planet itself has a radius rp and a mass mp. We know that when an object adds its velocity at a point in the orbit, the height of the opposite orbit will increase. Determine the...

Hello everyone, I know that GR equations are complicated and beyond my scope. But does GR give a simple gravitational equation: Force (as we know it) as a function of distance? (without any complicated tensors). - If yes. What is the equation? Does it give us something similar to Newtons...

It's a well known fact that acceleration due to gravity is independent of the mass of the accelerating body, and only depends on the mass of the body it is accelerating towards and the distance from it. One can prove this mathematically very easily. F=GMm/r^2 (equation 1) but also F=ma...

Density of the Sphere = 3M/4πR³ Mass of carved out sphere = density × 4π/3 × R³/8 = M/8 The position of center of mass of The Sphere {M(0) - M/8(R/2)}/M-M/8 -R/14 So total distance between centers of the two bodies is R/14 + 3R = 43R/14 So now I found force between the Mass 7M/8 (left out...

Book says that correct answer is d) but I can't understand why. If the result of gravitational and centrifugal force is 0N then there is no force that would keep those objects inside the spacecraft orbiting around the planet. Or am I just completely wrong? Thank you for your help.

i spoke to my proffesor about it but all he said was to put 1 in m1 and m2... for r^2 since it says to quadruple to just put 4^2 I asked about the G in the equation but he said not to worry about iit and pretend its not there...

><br/> >Mass M1 is held on a plane with inclination angle θ, and mass M2 hangs over the side. The two masses are connected by a massless string...

If the statement above is correct, I do not understand this concept. I guess by charging my phone I am not producing matter. Does it mean in this case, energy converts to mass (not matter)? Can someone please explain this?

What is the current scientific consensus on the gravitational force between matter and antimatter. Is it repulsive, attractive or zero?

This question is very confusing since I don't see two distinct particles that are exerting a gravitational force on each other. Also to complicate matters, a gas is made of many individual particles and I don't know how to determine the gravitational force on a single particle from so many other...

Hello everyone. Probably this question is trivial, but nevertheless I am confused about Newtons law of motion: $$F=G\frac{m_1m_2}{r^2}$$ Now, some sources say, that F is the force between the two masses m1 and m2. Other sources say, that F is the force that m1 exhibits on m2. But isn’t this a...

first to find the force by gravity, it would be 4 kg * 9.8 m/s = 39.2 N then solve for work using W= F*d*cos(theta) W = 39.2 N * 3 m * cos 28 = 103.83 J My confusion is do I use sine or cosine and what angle do I use, the actual angle of the incline or the angle between the mass and the...

First, start off with x and y directional forces F (Test object 1) - F x(Test object 2) I need help primarily with finding the horizontal component of the force from object 2. How do I find it and express it? Thanks

At first, I thought when the rod goes really far away from the particle, then L would approach to zero in a particle's reference view. As a result, the equation will be GmM/d^2. However, I just thought that L just remain as it is regardless of change in d, but not sure...

The correct answer is the second one. I honestly have no idea why this is so. I understand that the right rope has less tension that the left one since it's at a shallower angle from real world experience, but I don't really know why this is so, let alone how the forces compare to gravitational...

Ok the mass of light topic is too big so I'll start a new one.A photon has energy E = hfSo it has a relativistic mass given by m = E/c2so m = hf/c2so could I say that a photon of frequency f, at a distance d from a planet of mass M ,exerts a gravitiatonal forceFg= G*hf*M/d2c2would youa)...

Is the internal temperature of the earth factored into the calculation of it's gravitational force?Could there be some thermodynamic explanation of gravity?And what's with the inverse square of proportion law coincidence between gravity and electromagnitism?Use your key to open all doors of...

The mass of one small ball is 1.94 g, and the mass of another is 806 g. If the center-to-center distance between these two balls is 14.7 cm, find the magnitude of the gravitational force that each exerts on the other. (Exponential notation is input using the format: 3.45E-5 for the number 3.45 x...

I'll ask anyone interested to bear with the horrendous amount of maths here. There is a worthwhile result at the end of all this. Trust me on this.OK my bold assumption is as follows. Light, or photons, exerts a gravitational force on the universe around it. A photon with energy E has associated...

I know someone can answer this because it's not too hard. I just dont understand it at all.If you stand 1 km from the center of a typical mountain of mass 5x 10 11 kg, you�ll be gravitationally attracted to it. Likewise you�re attracted to the moon (mass 7.4 x 10 22 kg) which is 3.8 x 10 5...

Anyone know where I can find the derivation of the formula that says that all points inside a uniform sphere(like the earth, I know its not uniform), have zero net gravitational force acting on them. I can't find it anywhere and I can't derive it myself either.http://www.albinotreefrog.net

Is there any astronomical indication that gravitational force between dark matter might be weaker than between visible matter?

F=Gm1m2/r^2 2.67 = (6.67x10^-11)(m1xm2)/25000000 M1xM2 = 1 x 10^18 M2 = 1x10^18/M1 (Equation 1) From the question stem, we know M1 + M2 = 2.5x10^9 (Equation 2) So, substituting Equation 1 into Equation 2 we get: 1x10^18/m1 + m1 = 2.5 x 10^9 I'M STUCK FROM HERE ONWARDS... in the solutions...

Hello, I hope you are all very well ! Let's say a man, standing on point "0 m" throws a ball 10 m in the air. The gravitational force goes in the opposite (down (always)) of the action (up): I supposed it's -9.81 m/s². The same action but this time the man stands on the point "10 m" and the...

I think choice B is correct because when I draw the free body diagram of each object, there are three forces acting on each of them and the resultant force is towards the center. Choice C is wrong because the net field at center is zero. I think choice D is also correct because if the...

like a shot bullet or arrow has negligibly more gravitational force than a still bullet or arrow?, this is what I'm asking, m=e/c^2 F=Gm/r^2, thus, F=Ge/(c^2*r^2) where e represents the (mass of the object + energy added to the object) thus more the energy, more the gravitational force, even...

I suppose we can just find the net x components and y components and then go from there. Σ Fx = F(mass 1) - Fx(mass 2) G* (m^2)./d^2) - something I'm not sure how to express the component forces of the 2nd mass

Hi, I have always held (and still do I suppose) the view that gravity is much weaker than the coulomb electrical force due to the fact the equations are so similar you can just compare the constants from each equation showing that the graviational force is many orders of magnitude smaller...

Homework Statement Astrology, that unlikely and vague pseudoscience, makes much of the position of the planets at the moment of birth. The only known force a planet exerts on Earth is gravitational. (a) Calculate the gravitational force exerted on a 5.00 kg baby by a 130 kg father 0.200 m away...

I am attempting to prove Newton's shell theorem. There are multiple solutions to this problem, but I am attempting a solution involving adding up the gravitational force of an infinite number of infinitely small disks that are placed together (the discs facing a point mass "m") to form a...

A person of mass 60kg will weigh around 100N on the moon. This is roughly equivalent to the gravitational force on a 10kg object on Earth. Even if the forces acting on both are about the same, we don't see 10kg objects floating around on Earth whereas a man weighing 60kg can easily float on the...

Homework Statement I don’t understand why this would relate to cosine and not sine, if gravity is often assiciated in the up and down part of a free body diagram. Homework Equations Wg=mgdcos(theta)[/B]The Attempt at a Solution Is it because it would depend on your reference frame?