Gravitation Definition and 918 Threads

Homework Statement The problem is stated here: http://i53.tinypic.com/2wfl4jm.jpg Please take a look.

1. Two spheres having masses M and 2M and radii R and 3R, respectively, are simultaneously released from rest when the distance between their centers is 12R. Assume the two spheres interact only with each other and we wish to find the speeds with which they collide. Write an equation from one of...

1. Two spheres having masses M and 2M and radii R and 3R, respectively, are simultaneously released from rest when the distance between their centers is 12R. Assume the two spheres interact only with each other and we wish to find the speeds with which they collide. Write an equation from one of...

Homework Statement In a hydrogen atom a electron and a proton are 1.0 x 10^-10m apart. What is the force of attraction between the two particles? Homework Equations F=G m1 m2/r^2 The Attempt at a Solution electron: 9.11 * 10^31kg Proton: 1.67 * 10^-27kg so, Fgrav= (9.11...

I am struggling to understand Newtons law: F = ma = GMm/r^2 a = GM/r^2 In the above equation, the small m's cancel out to give a constant acceleration due to gravity from the perspective of big M. I consider a planet and a small moon (little m) a certain distance away from the planet...

Homework Statement Transplanertay tours promises tour participants a certificate to commemorate their passage from the stronger influence of Earth's graviational pull to the stronger pull of the Moon at the point where the two forces on your spaceship are equal. Where on the trip should you...

Homework Statement During a solar eclipse, the Moon, the Earth, and the Sun all lie on the same line, with the Moon between the Earth and the Sun. (a) What force is exerted by the sun on the moon? (b) What force is exerted by the Earth on the Moon? (c) What force is exerted by the sun on the...

Homework Statement A satellite of mass 4600 kg orbits the Earth (mass = 6.0 1024 kg) and has a period of 5500 s. (a) Find the magnitude of the Earth's gravitational force on the satellite. (b) Find the altitude of the satelite Homework Equations Kepler's Equation: R^3/T^2 Fg=...

A satellite is in a circular Earth orbit of radius r. The area A enclosed by the orbit depends on r2 because A = πr2. Determine how the following properties of the satellite depend on r. In each case, give the power of r, i.e., if the dependence goes as rn, give n. If there is no dependence...

Homework Statement A satellite in a circular orbit around the Earth with a radius 1.021 times the mean radius of the Earth is hit by an incoming meteorite. A large fragment (m = 65 kg) is ejected in the backwards direction so that it is stationary with respect to the Earth and falls directly...

Homework Statement What force does Earth exert on a 80.0-kg astronaut at an altitude equivalent to 2.5 times Earth's radius? Homework Equations FG = (Gm1m2) / r2 Radius of Earth: 6370 km Mass of Earth: 5.97x1024 kg The Attempt at a Solution FG = (Gm1m2) / r2 FG = (G x MEarth x 80...

First off this is not homework or coursework, just general interest. I've been looking to derive the rocket equation which includes the effects of Universal Gravitation. I've been able to derive it assuming near Earth gravity where g is taking as constant acceleration...

General relativity predicts that electromagnetic fields contribute to the stress-energy tensor, and that they therefore have gravitational fields. Kreuzer (1968) did laboratory experiments that were interpreted by Will (1976) as confirmation of this prediction in the case of the static electric...

Homework Statement Let a particle slides in a straight smooth tube passing obliquely through the Earth. Assuming no friction and no rotational effects. Describe the motion. Find Frequency and Period. Homework Equations F = -GMm/r^2 The Attempt at a Solution Don't know how to...

Gravitation and Electromagnetic forces are independent, correct? That implies.. Gravitation would exist even if Electromagnetic forces didn't. But, electromagnetic forces are responsible for existence of atoms.. and atoms are what make up the mass, no? And Gravitation exists because of Mass...

I'm a math major, but I really want to learn about general relativity (the 'real' GR, not the watered-down version that gets into popular science books) on my own. I'm not in any rush to learn it--i.e., I'm willing to work through a big tome like Gravitation over the course of, say, the next...

A skier lowers a cart 30m down a slope with a sontant speed. The cart has a mass of 90kg. The angle of the slope is 60 degrees. The coefficient of friction is 0.100. A)Find the work done by friction as the sled moves down the hill. B) how much work is done by the rope on the sled. C) What is...

3 10 kg spheres are located at the corners of a equilateral triangle of sides .5m. Calculate the magnitude of the total gravitational force exerted on one sphere by the other two. I used G = 6.67 x 10^-11. The answer I got was 4.62 x 10 ^-8. Can anyone confirm if this is correct, or explain how...

Homework Statement An artificial satellite of mass m of a planet of mass M, revolves in a circular orbit whose radius is n times the radius R of the planet. In the process of motion, the satellite experiences a slight resistance due to cosmic dust. Assuming the resistive force on satellite...

Homework Statement 2 particles of masses M and m are initially at rest and infinitely separated. When they move towards each other due to gravitational attraction, what is their relative velocity at any instant? Homework Equations The Attempt at a Solution The problem may be...

Homework Statement A particle is projected from the surface of the Earth with an initial speed of 4km/s. Find the max. height attained by the particle. Radius of Earth = 6400 km and g=9.8 m/s2 Homework Equations The Attempt at a Solution I have two approaches to this problem...

HI, I am new in this kind of programming ..this is my very first 2D game in OpenGl using Glut 3.7 (Win32 Console C++) and i have no idea how to apply projectile motion and gravitation on basket ball. game is simple.. Inputs Are Force and Angle.. and player has to throw the ball into the...

I apologize for my English, it's not my native language. Homework Statement There's three masses of 1 kg each set in an equilateral triangle of side length 0.8 meters. Mass m1 is located in coordinates (-0.4m, 0) and m2 is located in coordinates (0.4m, 0). What are the coordinates of m3? A...

How do we know that light travels on null geodesic in arbitrary curved spacetime. Could anyone give me reason for this assumption (many GR textbooks assume this without any justification). In flat space time the above fact may be proven by means of the Green function. It tells us that the...

I received this problem this week and no one in my class has been able to solve it. We don't need to solve it exactly, but we should provide a conceptual answer. I would really appreciate it if anyone could help me out. -The apparent weight of a person may vary in different latitudes due to...

Homework Statement Consider a hypothetical extra*solar world, planet X, that has 2.2 times the radius of the Earth and 2.5 times its density. What is the acceleration due to gravity on the surface of planet X? Homework Equations g=GM/r^2 The Attempt at a Solution I am not...

Can someone tell how antiparticles affected by gravitational force? The same way as particles or opposite? Thanks.

Hello, could you please help to clarifly the following. Do electromagnetic (e.g. light) and gravitational wavefronts caused by e.g. a supernova both appear at the same time seen from a distant observer perspective? Thank you!

While reading gravitation chapter I got some doubts, and that I am posting here. 1) Is there any meaning of "Weight of the Earth"? 2)At noon, the sun and the Earth pull the objects on the Earth's surface in opposite direction. At midnight the sun and the Earth pull these objects in the...

How does one show that dF = 0 is the geometric version of Maxwell's equations??

Homework Statement I am doing a lab-"Kepler's Laws and Newton's Law of Universal Gravitation". There is an image representing various positions, at equal intervals, of a satelitte in an elliptical orbit around the earth. A list of planets and their radi and periods are given. I have calculated...

Hy. I was wondering if the gravitation is too much on earth. What if on some other planets is less. How that affect life ?

Hi all, this will be my first physics qns:D more to come... I just learned that value of g at the equator is not exactly equal to the gravitational field strength. Can anyone explain with workings? i don't really understand my teacher workings. Also can i clarify if -We're assuming Earth...

1. Take the equation F=[G(m1)(m2)]/r2 2. Assume a single mass of 20 (units don't matter), which will be divided in the following ways: 2.1. System 1: m1=20, m2=0 2.2. System 2: m1=19, m2=1 2.3. System 3: m1=18, m2=2 2.4. System 4: m1=17, m2=3 . . . 2.11.System 11: m1=10, m2=10 Now... 3...

Homework Statement The average distance separating Earth and the moon is 384000km. What is the net gravitational force exerted by Earth and the moon on a 3.00 x 10^4kg spaceship located halfway between them. Homework Equations F=Gm1m2/r^2 G = 6.673x10^-11 earth mass = 5.98x10^24...

At the very bottom of the page they have that the straight line, using the definition of a vector as the derivative of the worldline is given as: P(0) + \lambda(\frac{dP}{d\tau})_o But since the worldline, P(\tau) is paramtrized by \tau and not \lambda, then shouldn't the equation be...

Homework Statement At a certain point between Earth and the Moon, the net gravitational force exerted on an object by the Earth and the Moon is ZERO. The mass of the Moon is 1.2% the Mass of the Earth. The centre to centre distance between the Moon and the Earth is 3.84*10^5 km. i) WHERE IS...

HI, According to GR, gravitation is simply the geometry bending. Does this also apply on Earth? We can stick on Earth, does it the force attract us?? Or is a geometry problem as well?? I get confused about this. Thanks Alex

Homework Statement Say, there are two bodies, mass m1 and m2, initially at rest at infinite separation. They start accelerating towards each other because of gravity. Express the relative velocity of approach as a function of the distance between the two bodies. Homework Equations Laws...

Homework Statement Two objects attract each other with a gravitational magnitude 1.00x10-8N when separated by 20.0cm. If the total mass of the two objects is 5.00kg what is the mass of each? Homework Equations Fg=G*m1m2/r2 G=6.673x10-11Nm2/kg2 I'm not real sure how to go about this...

In the example 12.5 (Section 12.3) in the textbook we ignored the gravitational effects of the moon on a spacecraft en route from the Earth to the moon. In fact, we must include the gravitational potential energy due to the moon as well. For this problem, you can ignore the motion of the Earth...

Hi Guys I am in year 12 and have my exam shortly would just like to ask a question to do with gravity. A small satellite orbits Mars. It has a kinetic energy of 3.0x10^10 J, and is at a constant distance of 8.0x10^7 m from the center of Mars. What is the weight of the satellite at this height?

Okay, this is going to be one hell of a skeptical thread. Being a musician and all i have music software that enables me to manipulate sound As of now, I've manipulated a Bass note in C to a harmonic oscillation(sp?) ranging from >0hz to 500hz. I've got it just to were the noise won't...

Homework Statement At what height will the acceleration due to gravity will fall to 25% that of the Earth's surface? Homework Equations g= GM/R^2 The Attempt at a Solution

gravitation lab for online simulation--equation derivation help? Homework Statement To start with, you can access the lab here: http://phet.colorado.edu/teacher_ideas/view-contribution.php?contribution_id=690" . I'm having trouble with the "Activity 4" part. It reads: "Change the number of...

Homework Statement A spaceship is launched and starts moving directly towards the Moon. At what distance from the Earth will the pull of the Moon, on the spaceship, exceed the pull of the Earth? Ignore the effect of the sun in this calculation. Homework Equations F=G(M1M2/r^2) The Attempt...

On the full moon day the moon is closer to Earth so the gravitation of the moon make the gravitation of the Earth on us less strong. Is it true ? Thanks !

Homework Statement What is the kinetic energy and total mechanical energy of a binary system of identical spheres orbiting around their common center of mass? M = mass R = radius Homework Equations Force of gravity = GM^2/2R K = 1/2MV^2 The Attempt at a Solution I don't know whether...

Hey! My teacher told me that there is a correction term to Newtons law of gravitation when you take general relativity into account, somthing lik: F=G\frac{M_1M_2}{r^2}+F_{correction} I been searching like mad but can't find it on the internet anywhere. The only things I found was a set of...

How the mechanism of gravity can converted to the electric energy?How much the power result? Please shared to me, if you have any literature..