Gravitation Definition and 918 Threads

Hello! I just had an stupid idea and i want to know what do you think of it. Let's say thers an creature who is living in 2d world. An 3d world hole in his 2d world plane would feel for this creature like gravitation. Wouldnt it? An 3d mountain would feel for him like ant-grav or somethink like...

A couple of questions about Universal Gravitation.. When satellites are launched with velocities greater or lesser than the required launch velocity [Underroot(G*Mass of earth/Radius of Earth)], their orbits become elliptical with the Earth as the near or far focus. Why? Also, 'The Earth...

Lets say we have three spheres all of uniform density and equal mass, However, sphere A has a rotational period of 16h, B has period of 24h and C has period of 48h. So which one has the greatest acceleration (g value) at the poles and at the equator.

A solid sphere has a uniform density, a mass of 17 kg and a radius of 2.2 m. ============= a) What is the force due to gravity from the sphere on a very small object of mass 21 grams located 1.1 m from its center? b) What is the force due to gravity from the sphere on a very small object...

A 140 kg rocket is moving radially outward from the Earth at an altitude of 200 km above the surface with a velocity of 3.5 km/sec. At this point, its final stage engine shuts off. a)Ignoring any minor air resistance, what is the rocket's velocity 1000km above the surface of the earth? b)...

A neutron star is formed when a star has burned all its nuclear fuel and begins to collapse in upon itself. It then packs roughly the mass of our Sun into a region with the same radius as that of a small city while continuing to spin at very rapid rate. Let's say you have a neutron star with a...

Quantum Gravitation String Theory: Planck's Radius: r_p = \sqrt{ \frac{ \hbar G}{ c^3}} Minimum observable length for a quantum string: r_m = 2 \sqrt{ \alpha '} Planck's Radius is minimum observable length for a quantum string: r_p = r_m Planck area of the hyperspace amplified...

Ok, here's the problem: Neutron stars are extremely dense objects that are formed from the remnants of supernova explosions. Many rotate very rapidly. Suppose that the mass of a certain spherical neutron star is twice the mass of the Sun and its radius is 5.0 km. Determine the greatest...

I'm having a little bit of a problem with this one. Here's the question: X-ray pulses from Cygnus X-1, a celestial x-ray source, have been recorded during high-altitude rocket flights. The signals can be interpreted as originating when a blob of ionized matter orbits a black hole with a...

Gravitational slingshot How does this work exactly? Where does my analysis go wrong? I know it is used to speed satellites up, but its name alludes to a permanent improvement in speed. The way I see it, you would get a slight benefit in journey time as long as the satellite is within the...

Hi All, Blackholes will curve the space-time in a way so that even particles moving with speed of light are trapped. It's presence is detected by the gravitational force it exerts. So if there were particles like gravitons which would defenitely travel less than or equal to 'c', those also...

1)Is there any way to derive an expression for the mass of a satellite in an orbit?? 2)A projectile is fired with a velocity of 10 m/s at an angle of 30 to the horizontal. When it reaches the maximum height,an object dropping 40 m above the projectile, collides with the projectile.Find the...

According to Newton's Law of Gravitation, all objects with mass attract one another. This law implies that all of the atoms that make up a star, such as our sun, are gravitationally attracted to one another. How is a star able to resist collapsing under its own gravitational attraction? [?]...

force, can force change direction, if so can gravitation force change its direction,

I ran across this paper some time ago. I would be interested in any comments that you may have. http://www.laboratory.ru/articl/hypo/eax060.htm

In the following problem, I got that the velocity is 5609m/s but the answer key says that the velocity of the rocket is 3950m/s. I know both answers can be calculated but I don't understand why the radial distance would be the distance from the rocket to the Earth's surface. I personally think...

More years ago then I care to think about I discovered a contradiction in the way we think about Gravity. I called it the Paradox of Gravitation, and I decided that if it could be unraveled we could gain insight into the nature of Gravity. The paradox is this, people think of Gravity as being...

the first principle of dynamics by mua dynamics is a field in physics dealing with the matter in motion with questioning the cause of the motion. as a most important law in this field there is the second Newton's law. but unfortunately this law is not valid. i want go thru reproving that claim...