Gravitational force Definition and 491 Threads

I want a better visual model of what Newton's gravitational force formula represents: (G⋅m1⋅m2)/d2 But there are two contradictory things that I'm having trouble reconciling: Multiplying the two masses shows a relationship between the two point sources, but using the area of the sphere to...

I know gravity is a conservative force field and can be treated as such for all intents and purposes, but I was just thinking that in order to show that a vector field is conservative that vector field must be defined everywhere (gravitational force field is not defined at r=0). I was thinking...

Hi THere! can somebody please tell me why gravitation and electrostatic force exist? why two charges attract or repel each other, and why two masses always attract each other?

Homework Statement Imagine you could place 1g of electrons 1.0 m away from another 1g of electrons. calculate the electrical force and gravitational force between them. Homework Equations fe= kQ1Q2/r^2 fg=Gm1m2/r^2 The Attempt at a Solution So the number of electron is N= 0.001 /...

Hello, We know that light get bent near stars (because of its gravitational force), and in fact it cannot escape the gravitational forces of black holes. We also know from Newton's laws of gravity that the gravitational attraction between any two objects is ZERO if any mass is ZERO. We also...

Am I correct in thinking that the force of gravity between 2 test objects at rest on a planet's surface is less than it would be for the same objects at rest in deep space? I understand that this occurs because in GR gravitational potential has a mass value which is lost on the surface, while...

Just a little curious. What formula did Sir Isaac Newton used to find out the exact value of Earth's gravitational force ? Can we apply that formula to find out the gravitational force of other objects ? Let's say, calculating the gravitational force that my bottle has or our body. I know that...

1. Problem A rocket has landed on Planet X, which has half the radius of Earth. An astronaut onboard the rocket weighs twice as much on Planet X as on Earth. If the escape velocity for the rocket taking off from Earth is v , then its escape velocity on Planet X is a) 2 v b) (√2)v c) v d) v/2 e)...

Hi! So I learned Newtons Law of Gravity and used the numbers to calculate that the acceleration due to the attraction between masses is 9.8m/s/s. Hooray! This is what I've learned is the acceleration due to gravity. However, does the rotation of the Earth and the subsequent centrifugal force...

Homework Statement As a moon follows it's orbit around a planet, the maximum gravitational force exerted on the moon by the planet exceeds the minimum gravitational force by 11%. Find the ratio rmax / rmin, where rmax is the moon's maximum distance from the center of the planet and rmin is...

I considered a free falling object in the Schwarzschild metric at rest at infinity and found as approximation the acceleration : $$\frac{d^2 r}{dt^2}\approx -\frac{GM}{r^2}+\frac{3G^2M^2}{r^3c^2}$$ This would mean if there are no sign error in some sense that the force becomes repulsive at...

Homework Statement Jupiter has a core of liquid metallic hydrogen, with uniform density $\rho_c$, with radius $R_c$. This is surrounded by a gaseous cloud $R_g$, where $R_g>R_c$. Assume the cloud is of uniform density $\rho_g$. The problem also specifies that we are to assume both regions of...

This is an excerpt from "Introduction to Mechanics" by Kleppner and Kolenkow: "The reason why gravitational force vanishes inside a spherical shell can be seen by a simple argument due to Newton. Consider the two small mass elements marked out by a conical surface with its apex at ##m##. The...

Homework Statement A 500 kg satellite experiences a gravitational force of 3000 N, while moving in a circular orbit around Earth. A) Find the radius of the orbit B) Find the speed of the satellite C) Find the period of the orbit I found this set of questions a bit trickier, although am...

A large spherical planet of radius R made of a material of density d, has a spherical cavity of radius R/2, with center of cavity a distance R/2 from the centre of the planet. Find the gravitational Force on a small mass m at the centre of the cavity

Homework Statement [/B] 1)Which describes the 1D gravitational force in this figure. (+x is to the right.) a)Something else. b)Fgrav=−GMmx2 c)Fgrav=+GMmx22)In moving the little mass m from x1 to infinity the force of gravity does _____________ work. a) positive b) negative c) no I added an...

Homework Statement Mass M is distributed uniformly along a line of length 2L. A particle of mass m is at a point that is a distance a above the center of the line on it's perpendicular bisector. For the gravitational force that the line exerts on the particle. calculate the components...

1. The problem statement, all variables and given/known dat Three solid spheres of lead, each of mass 9.8 kg, are located at three corners of a square with side lengths of 50 cm. A small object is released at the forth corner. Considering only the gravitational forces among the four objects...

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=...

About: As a project, I'm trying to solve for the approximate radius and mass of a approximately earth-sized planet, Mann, from Interstellar. According to what was provided, g = 7.84m/s2 The solid part of the planet is composed of a honeycomb of rock and ice The space inside the honeycomb is...

Homework Statement What is the magnitude of the net gravitational force on the m2=5kg mass? Assume m1=25kg and m3=15kg. https://session.masteringphysics.com/problemAsset/1383524/6/13_P28.png Homework Equations F=GMm/r^2 The Attempt at a Solution First I find the angle between m1 and m2 which...

Homework Statement Two bags, each containing ten oranges of equal mass, are hung 4.0 m apart. Describe two situations, one involving mass and the other involving separation distance, that would quadruple the gravitational force exerted by one bag on the other. Explain your answer...

Homework Statement Homework EquationsThe Attempt at a Solution For a), I initially tried to consider the component of the gravitational force of the moon acting normally to the Earth's surface. This would be F=F_0 cos(theta) where theta is the angle between a horizontal line going through A...

I was thinking about the motion of two stars in a binary star system, but there is something I cannot quite figure out. Suppose you have a binary star system with two stars masses m1 and m2 with m2>m1 so that m2 is closer to the centre of mass of the system. Then when the two stars are as far...

I kind of have a stupid question. How much more massive would the Earth have to be for the average person to weigh about 50 more pounds? How much bigger could the Earth's diameter be? Thanks.

Homework Statement A single charge q1 = 1.10E-7 C is fixed at the base of a plane that makes an angle theta with the horizontal direction. A small ball of mass m = 1.75 g and a charge q2 = 3.30E-8 C is placed into a smooth frictionless groove in the plane that extends directly to the fixed...

Homework Statement Please look at the picture. Homework Equations $$F=\frac{GMm}{d^2}$$ The Attempt at a Solution I'm stuck with this problem , because I cannot imagine it properly. If I say that the mass m is in between the two masses , I cannot find d in the choices ,, Any help please!

Hey Guys! I've been doing a few equations in regards to planetary escape velocity and gravitational force. The below links have the escape velocity of listed planet on the left side of the board, the gravitational force between the Sun and given planet on the right side. In the middle of the...

I am working on a problem to sate my own curiosity. :) My mass is approximately 85.1 Kg. The Earth's mass is approximately (5.972x10^24 kg) and the distance between our center of masses is roughly the same as the Earth's radius of (6371 km) so I was wondering; what would the Earth's...

Homework Statement Given that the force of gravitation between Planet A (the one in the left side of the drawing), Fa=3000/da2 and the force of gravitation between Planet B and the rocket, Fb= 6000/ db2. Assuming that the three bodies involved is in stationary. What are the distances (ranges)...

Gravity has such a long range and such a weak magnitude . Might it be due to the fact that it's acting on the three-dimensional vehicle as a mode exerting its force this way gives limitations, its inability to conserve energy due to friction resistance among others. Also is gravity applied...

Homework Statement A large telescope of mass 8410 kg is in a circular orbit around the earth, making one revolution every 927 minutes. What is the magnitude of the gravitational force exerted on the satellite by the earth? M_E = 6.0x10^{24} kg m_s = 8410 kg T_s = 927 min = 55,620 s G =...

Homework Statement I am trying to derive the formula for simple harmonic motion of a mass hanging on a spring. I understand the derivation for the situation when the mass and the spring are on an horizontal table. Then I go about deriving the same formula for the situation when a mass is...

Hi Guys, I'm working on the theory for a piece of gym equipment, but I am afraid my physics-capabilities are somewhat limited. In order to illustrate my question, I have made a drawing, please look at the attachment. Excuse my english as well, it is not my first language. So on the...

When I was in introductory physics I remember being told that the net force (gravitational for example) inside a shell is always 0. I always felt that, intuitively, this would only be true at the center of the ring. Not sure what made me think of it today, by I decided to sit down and do the...

Hello everybody. I registered today in this forum and this is my first post. I'm Italian, therefore sorry for my ugly english. Studying physics (for my personal curiosity) I proposed myself two problems I couldn't solve. One of these, is: at the point x=0 (of a one dimensional space) there...

Homework Statement Three identical very dense masses of 8000kg each are placed on the x axis. One mass is at x1 = -140cm , one is at the origin, and one is at x2 = 440cm . What is the magnitude of the net gravitational force Fgrav on the mass at the origin due to the other two masses? Take...

Hi all, This is Newton's universal law of gravitation: F = GMm/r2, where r is the distance between the centre of the two bodies. Therefore, considering two objects in mutual gravitational acceleration, with only linear motion and acceleration, they shall be moving in closer and closer. Since...

Homework Statement The space shuttle Endeavor is moving at a speed of 27870 Km / h. At takeoff, its mass is 2, 28 * 10 ^ 6 kg, however, its mass decreases as it uses its fuel: the engine burns liquid oxygen which has a density of 1141 kg / m^3, at a rate of 1340 liters per second. Calculate...

Homework Statement Let there be a Voyager 5 with two Earth's(I mean they have the same mass and density etc) At start,Voyager 5 will be stationary. I want to calculate the path of the Voyager and if possible,draw it on a graph. Homework Equations ##F=\frac{GMm}{r^2}## The Attempt...

We all can measure the mass of a body by any common instrument like Spring Balance. But if we go from one place to another place the gravitational force will change, like if we go from 1st floor to 10th floor or from coastal region to plateau region. The gravitational force depend on the...

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...

When Earth pulls a mass with gravitational force why does the energy of the earth-mass system decrease? Isn't work just transfer of energy meaning constant overall energy?

Hi everyone, I'm a college student enrolled in an astronomy course, and simply put, science and math in general are both quite possibly the two things I'm worst at! Anyways, I have a test coming up and our professor gave us a practice test, and after a lot of studying, I was able to figure out...

So, I asked myself the question, "why does the Earth's force of gravity effect us so dramatically on the surface of the earth, but seems nonexistent while just a couple hundred miles up?" I answered that question myself, after thinking more about it, because the idea of an orbit is that you...

Homework Statement The drawing (not to scale) shows one alignment of the sun, earth, and moon. The gravitational force vector F SM that the sun exerts on the moon is perpendicular to the force vector F EM that the Earth exerts on the moon. The masses are: mass of sun = 1.99 1030 kg, mass of...

http://www.aapt.org/physicsteam/2012/upload/exam1-2011-1-3-answers_1.pdf Homework Statement You are given a large collection of identical heavy balls and lightweight rods. When two balls are placed at the ends of one rod and interact through their mutual gravitational attraction (as is...

This is a purely conceptual question that I’m having trouble understanding. From what I understand, anytime an energy transfer takes place as work, you can say that something has done work on something else. For example, if the gas in a cylinder with a piston on it pushes back the atmosphere...

Suppose I have two object. One is 1 kg and other one is 2 kg. And separation between two object is 10 m . By gravitational force both objects attracts towards each other with some speed. But i want to know with what velocity they are moving towards each other. Or is there any equation to find...

Homework Statement A particle with charge q = 4.00 10-6 C and mass m = 1.30 10-4 kg is moving parallel to the Earth's surface at a speed of 1000 m/s. What minimum strength of magnetic field would be required to balance the gravitational force on the particle? Homework Equations Not...