Universal Definition and 488 Threads

The metric due to the gravitational field of a spherical mass is described by the schwarzschild metric ds2 = c2 (1 - R/r) dt2 - (1 - R/r)-1 dr2 - r2 d\Omega 2 Where \Omega is the solid angle, and R is the schwarzschild radius. What are the physical meanings of the coordinates t and r...

not sure if this question has been asked before, but is the weight of an object the same in a vacuum compared to weight in an atmosphere. the concerns of this question is that do we need to consider that our atmosphere provides some boyancy on our mass to change the value of weight.

Homework Statement Given: G = 6.67259 × 10^−11 Nm2/kg2 A small Moon of a planet has an orbital period of 2.08 days and an orbital radius of 5.04 × 10^5 km. From these data, determine the mass of the planet. Answer in units of kg. Homework Equations FG=FC FG=Gm1m2/r^2 FC=mv^2/r The...

Update: Thanks for the help! I'll work on it...

1. Homework Statement a spacecraft of mass 1000kg, in an elliptical orbit about the earth, at one point its distance from Earth is 1.2 x 107 meters and its velocity is 7.1 x 103 meters per sec, and the velocity vector is perpendicular to the line connecting the center of the Earth to the...

Homework Statement a spacecraft of mass 1000kg, in an elliptical orbit about the earth, at one point its distance from Earth is 1.2 x 107 meters and its velocity is 7.1 x 103 meters per sec, and the velocity vector is perpendicular to the line connecting the center of the Earth to the...

Homework Statement A planet has twice the mass of earth, but both planets share the same acceleration of gravity. The radius of the new planet in terms of the radius R of Earth is...? Homework Equations F=G(m1m2/r2), G being the universal gravitation constant The Attempt at a...

I was reading about Dr Royal Rife and his universal microscope there and the author of the article claimed that universal microscopes can be used to view viruses without killing them like electron microscopes do. Is this true? Also are these universal microscopes still in use today? Before now...

I'm trying to understand the basics of gravity. Newtons law of universal gravitation gives us : F1 = F2 = G (m1m2)/r2 Now on Earth you can simply that down to F = mg where g = G (mearth/R2) But using f = mg, a heavier object say a tennis ball should fall faster than a cannon ball. But...

What are the pros and cons for transforming into a single payer system?

1. This only relates to a homework assignment, my curiosity lies in the effects of increasing the magnitude of G. Would this affect the Earth's orbiting of the sun? I assume that individuals an objects would experience gravity differently but I do not understand how specifically. Would their...

hello, I'm not saying that Newton's law of universal gravitation is really wrong but there are phenomenons which i don't think the law is really correct and i want someone to help me. There might be explanations but i don't really know any explanations right now so an explanation would be...

Newtons universal constant is very complicated due to that i am new to modern Earth science i searched on the net and the results were countless here is the common answer 1-G=6.67*10(squared negative 11)m(cubed)kg(squared negative 1)s(squared) someone please tell me what all this means and how...

question about math as an universal language Hi I apologize if this is in the wrong forum, my first time here I have some interest in thing like SETI and was curious about mathematics, as a universal language to communicate with ET, using prime numbers and such As math is based on...

Homework Statement Does anyone know what the universal graviation constant is in english to 7 significant figures. metric is around 6.67x10^-11 and 1kg = .0685 slug. In the english system the constant is 3.43x10^-8 but I need to get it to the right sig figs. Can anyone help out on this. I...

Hi all, Does Newton's law of universal gravitation depend on the geometry of the manifold? For example, what happens to formulas if we take the projective plane as our universe? How can one model "the mass" on the projective plane or on torus? I am a math grad with very elementary...

What is Universal weak coupling hypothesis?

Homework Statement A 450kg satellite is to be placed at an altitude of 2.45 x 10^6m above the Earth surface. Calculate the period the satellite will have when orbiting at that altitude. Homework Equations m2g = Gm1m2/R^2 = m2v^2 = m2(4pie)^2 R /T^2 = m2 2pie v/T Ac=4pie ^2 R / T^2...

Here is the succinct story of apple which fell on Sir Newton. Since both apple and Earth attract each other with a force equal in magnitude from both sides but apple move faster towards Earth because of its greater acceleration than negligible acceleration of earth. So Newton derived the...

It sounds like it should be a big field but despite its name, it doesn't seem to be studied by many people? Why?

Homework Statement I am to compute the homology groups H_*(\mathbb{C}P^2 \times \mathbb{R}P^2; \mathbb{Z}_2), with coefficients in \mathbb{Z}_2. Homework Equations Kunneth formula and universal Coefficient theorem The Attempt at a Solution First I need the homology groups...

Homework Statement An object of mass 40.0 kg rests on the surface of a planet with a mass of 8.2 x 1022 kg and radius 3.6 x 105 m. a) calculate the force of gravity acting on the object. b) Determine the gravitational field strength "g" at the planet surface. c) Calculate the force of...

I read Somewhere that the universe is expanding due to dark energy but how can dark energy create space and time?

Homework Statement What does the R in the ideal gas constant do. I know its a proportionality constant and it comes from a variety of equations and is related to Boltzmann, but what does it do physically?

Homework Statement Two identical lead spheres are 14cm apart and attract each other with a force of 0.30(myu)N . What is their mass? Homework Equations F = GMm/r^2 The Attempt at a Solution not sure but : let myu = u. .3uN = GMm/r^2 .3umg = GMm/r^2 u = 10/3...

Homework Statement Mercury's orbital speed varies from 38.8km at aphelion to 59.0km at perihelion. If the planet is 6.60*10^10m from the Sun's center at aphelion, how far is it at perihelion? Homework Equations v = sqrt(GM/r) (speed,circular orbit) The Attempt at a Solution...

Homework Statement A sensitive gravimeter is carried to the top of Chicago's Sears Tower, where its reading for the acceleration of gravity is 0.00136 m/s^2 lower than at street level. Find the height of the building. Homework Equations F = GMm/(r^2) and maybe K + U = K_o + U_o...

Homework Statement Neutron stars, such as the one at the center of the Crab Nebula, have about the same mass as our sun but a much smaller diameter. If you weigh 650 N on the earth, what would be your weight on the surface of a neutron star that has the same mass as our sun and a diameter...

Could it be that the universe is collapsing upon us without us yet knowing since the nearest star to us is about four light years away and therefore we have no present way of knowing what has happened during the last four years beyond that nearest star?

Hi, how can one define the concept of subgroup in universal algebra? is it possible at all? The problem is that in universal algebra the concept of group is defined by assigning to the inverse element and to the identity element, respectively an unary-operator and a nullary-operator. I am not...

Homework Statement Mars travels around the Sun in 1.88 (Earth) years, in an approximately circular orbit with a radius of 2.28 x 10^8 km Determine a) the orbital speed of Mars (relative to the Sun) b) the mass of the Sun Homework Equations acceleration centripetal = 4(pi^2)(r) /...

Homework Statement The mass of the Moon is 7.36 x 10 ^ 22 kg. At some point between Earth and the Moon, the force of Earth's gravitational attraction on an object is canceled by the Moon's force of gravitational attraction. If the distance between Earth and the Moon (center to center) is 3.84...

There's a handful of cosmologists and QM types who claim "the universe computes". There's another crowd who insist this is rubbish - the universe isn't a computer. However, it certainly appears to be 'computational'; this is demonstrable: if we can write a program that simulates a real...

Universal joint/ball bearing... controlled rotating arm for a furniture fitting Hello forum, I need your help on a furniture project we are developing in the office. its basically a floor standing lamp which needs to have a user regulated rotating arm. We are right now looking at different...

It is said that the universe began as a single tiny speck that suddenly expanded outward in all directions. It is also said that the universe is not expanding away from a particular point in space. These two statements are mutually incompatible. I await your reply with interest as you seem to...

Ok, I am not the best man at math but would like to understand the principles behind these sciences. However these terms are really messing me up. Please someone out there help. 1.) Is there a difference between Quantum theory and Quantum Physics 2.) What is the difference between...

Are there any books, written for the layman, which talk about observable effects that might be caused by our 5 (4 + time) dimensional portion of the universe moving through the larger universe. "Universe in a Nutshell" -Hawking, talks about how gravity may transend branes. Are there others?

Homework Statement Some people say that the tides on Earth are caused by the pull of the moon. Let us investigate whether this is true. (a) Determine the forces that the moon and the sun exert on a mass, m, of water on Earth. Your answer will be in terms of m with units of N. (c)...

Homework Statement Three(3) 10kg spheres form a triangle with the first sphere being at the top, the second sphere being at the bottom right cornern and the third sphere being at the bottom left corner. All sides of the triangle are 1.0m. Calculate the net gravitational force on the 3rd...

Would a universal open-source blueprint/design posted online be helpful to engineers? One reason nuclear power expensive is that there is little duplication in designs, and design costs are expensive. Would following what Linus did for Linux kernel help? First, one standardized universal...

1. Homework Statement Two "swarms" of krill each contain 1.200×107 identical individuals. The centers of gravity of the "swarms" are 15.0 meters apart. By what factor will the gravitational force of attraction between the two "swarms" change, if 9.231×106 new krill join each "swarm?" Use...

If in the future humans master time travel, might it be valuable to know a Universal Reference point that is common to both the present and past coordinates in space and time. For example, say we designated a single point on Earth from which all other relativistic effects are to be measured...

1. Planet A has a period of 1 year and an average distance from the sun of 1.63 × 1011 meters. If the average distance from the sun for planet B is 0.53 × 1011 meters, what is its period to the nearest hundredth of a year? 2. Two objects attract each other gravitationally with a force of when...

Homework Statement http://i241.photobucket.com/albums/ff4/alg5045/1012540B.jpg Consider the Earth following its nearly circular orbit (dashed curve) about the sun. The Earth has mass 5.98 *10^24 kg and the sun has mass 1.99 *10^30 kg. They are separated, center to center, by r=93 million...

Just a quick question: the transition between pre-big bang to post big bang (if it occured) required a change in physical constants (our universe is ever-expanding while the preBB universe was not). How can these constants change themsevels into new constants like that? This would seem to...

At what center-to-center distance from the Earth would a 0.9 kg mass weigh 0.9 N? I used equation g = GM/r^2 to get an answer of 8.17 X 10^-6 which is incorrect. Am I using the correct formula? Thanks

hey i have 2 very simple questions i can't seem to do. 1) determine the speed of the Earth around the sun... 2)The asteroid Pallas has an orbital period of 4.62 years. find the semi-major axis of its orbit. i no these r simple but i just can't seem to get them can someone help me or...

I am trying to show that if X is a topological space, ~ an equivalence relation on X and q:X-->X/~ the quotient map (i.e. q(x)=[x]), then the quotient topology on X/~ (U in X/~ open iff q^{-1}(U) open in X) is characterized by the following universal property: "If f:X-->Y is continuous and...

Hello everyone... I am new in engineering and I've given a topic about 'Universal Coupling'. But when do some research with Google, it seems don't have some information about the topic. Is anyone can help me to find some link or information? Is universal coupling = universal joint? Thanks...

Assuming the eventual heat death of the universe, would there be a time when all matter becomes superconducting, or manifests as quantum condensates?