What is Attraction: Definition and 302 Discussions

A tourist attraction is a place of interest where tourists visit, typically for its inherent or an exhibited natural or cultural value, historical significance, natural or built beauty, offering leisure and amusement.

View More On Wikipedia.org
1. B Help with science experiment magnets/force/acceleration/speed

Sorry, I guess I should have remembered all of this from my school days, but right now I have forgotten so much that I need some help. I am developing some simple experiments for school children (age ca. 12). This one involving magnets. I am not asking for detailed calculations, that is way...
2. B Magnetic attraction force Question

Other than the most simple school stuff of attraction, repulsion and "lines of force", I've never studied magnets. Hence this question. On the left we have a disc magnet diameter D attracted to a much larger lump of steel with force F (when there is no gap between)...
3. B Am I attracted to a hydrogen atom 1 billion light years away?

Just a quick question, are we attracted by a hydrogen atom billions of light years away by gravity or is my gravity completely masked by earth's gravity and so I am not attracted by the hydrogen atom? I am talking on a very very very small and incomprehensible scale.
4. I Magnetism: Same Pole Repulsion & Heteropolar Attraction

We know that the two magnets have same-pole repulsion and heteropolar attraction; In most parts of the planet, a magnet is hoisted with a thin wire, one side of the magnet will point to the guide, and the other side will point to the north; If you come to the magnetic pole of the earth and place...
5. Masses colliding due to gravitational attraction

When one mass is held fixed, the other mass acquires a speed v from gravity. I don't understand the following explanation: When both masses can move, they share the kinetic energy, so both have speed v/√2, so the relative speed is √2v. Hence to collapse the same distance r, the latter case will...
6. I Gas molecular attraction in the sense of Newton's law

Hello What experiment or observation shows that for atoms, molecules or masses of gas, there is attraction in the sense of Newton's law (universal attraction)? Bernadette
7. B Do forces of attraction really exist or are they just an illusion?

I wonder if forces of attraction really exist. Can two things separated by vacuum get attracted? It seems impossible.
8. B Why are gravitons needed to explain gravitational attraction?

Hi! Isn't gravity just a smaller object moving toward the lower energy state created by a larger object (time slows down the closer you are to a massive object)? Why do we need a force carrying particle for gravity?
9. B Why can't gravity be just a form of magnetic attraction?

Based on the photo electric effect. Maybe its perception that is the problem? Charge doesn't travel through a vaccuum. Electro magntic waves alway carry photons. Photons can make charge. Charge creates magnetism? Would explain why Coulumbs equation is the same as the one for gravity but on a...
10. B How does curvature of spacetime affect the motion of test particles?

If I had a chart of Cartesian coordinates and it had four axis's, t, x, y and z, how would I induce motion of a test particle by curving those axis's ? If the test particle was standing still and only moving in the t axis, how do i get it to move in the other axis's, x, y, z. I can understand a...
11. B Analogies for Gravitational Attraction in Physics

I am thinking of the mechanism that causes mass-energy to curve spacetime We have the Wheeler (was it ?)description, viz approx "mass tells spacetime how to curve and spacetime tells matter how to move...". Are there any analogous circumstances in other areas of physics where all (or a...
12. Dielectric and Attraction Between Oppositely Charged Plates

I am not able to intuitively understand the reasoning behind why the presence of dielectric between oppositely charged plates, let's say, reduces the force of attraction between the plates. I understand to some extent that electric field lines prefer to flow through dielectric (or insulator)...
13. Magnetic Attraction: Watching Magnets Move in Unison

so I toke three magnet, two smell magnet and big one so the big one is attractive both of small onces so it order like -(+-)+ . I toke the small magnet close to the edge of the range magnetic and lift it so the magnetic field is preventing it from falling because the magnet is trying to flip...
14. Magnetic attraction / repulsion from the Lorentz force

I'm trying to understand how the Lorentz force can explain why magnets attract and repel. The explanations that I have found have mostly involved the magnets moving in a way that decreases the forces between them ( ) but I have not been able to find any intuitive explanation involving the...
15. Coulomb's Law problem: Force of attraction between the two singly charged ions

In a salt crystal, the distance between adjacent sodium and chloride ions is 2.82×10^−10m. What is the force of attraction between the two singly charged ions?
16. Irodov problem 1.12 — A 3-body gravitational attraction problem

The thing is, I've already looked up at the solution online at it's t= 2a/3v. But I've approached it a different way and I can't really tell what I'm doing wrong, my solutions gives out t= (a/√3v )* (π/3),I don't know what's wrong with it. Here's my approach: The points will meet at the...
17. Exploring the Physics of Attraction & Repulsion: A Feynman Lecture

"Suppose we have another ther charge some distance away. Would it feel any attraction? It would feel practically none, because if the first two are equal in size, the attraction for the one and the repulsion for the other balance out.Therefore there is very little force at any appreciable...
18. Gravitation attraction of a mountain

I tried to solve for mass of the mountain by: (mass of ball) (9.8m/s^2)= G(mass of ball)(mass of mountain)/ (15000m)^2 The mass of the ball cancels out leaving with mass of mountain=33.04 * 10^(18) kg.
19. Magnet's attraction force on a piece of iron

Hi everyone, Please describe the process accures when placing an iron piece in front of (north pole) natural magnet bar, and how the attraction force is created. Also, to calculate the force magnitude (coulomb law for magnetism formula) how can I determine the piece of iron pole intesity (m)...
20. Magnetic attraction and repulsion equivalence

Equations of attraction or repulsion can get very complicated when the field shapes and densities are not identical. Intuition would hold the forces to be the same, but in on closer examination the field shape of two repulsing magnets looks entirely different from two attracting magnets. I...
21. B Gravitational attraction of 2 equal masses

Hi. If 2 equal masses are placed at rest ( an arbitrary distance apart ) on a horizontal friction-less surface do they accelerate from rest towards each other until they collide ? Thanks
22. B Galaxy Expansion or Attraction?

First of all, sorry for my naive question here which likely doesn't make sense. The universe is currently expanding with galaxies receding from each other at increasingly faster pace. Is it possible that the universe is a closed hypersphere system, where galaxies are actually not actively...
23. Attraction and repulsion of plates in capacitors

If we make far away the two plates of an ideal parallel -plate-capacitor, which are connected to a battery, the stored energy decreased according to the energy consideration because capacity decreases while the voltage between the two plates is unchanged. Therefore, according to the energy...
24. A Hamaker constant and effective attraction

Hello, According to the following equation describing the effective Hamaker constant of two identical bodies immersed in a liquid : AALA = (AA1/2 - AL1/2)2, for high values of AL, the effective attraction of the A-like media is larger than in vacuum. How is this possible physically ?
25. I Calculating recession vs attraction

How does one calculate the distance from a galaxy or galaxy cluster where recession due to dark energy begins and "attraction" ends?
26. Variation of gravitational attraction between Sun and Earth

Homework Statement Distance Earth-Sun at perihelion = 1.471×108 km Distance Earth-Sun at aphelion = 1.521×108 km Sun mass = 2.0×1030 kg Earth mass = 5.972×1024 kg G = 6.67×10-11 m3/kg⋅s What is the change in Newton of the attraction force between the Sun and the Earth from the perihelion to the...
27. Force between Parallel Current Carrying Wires

Homework Statement Two parallel wires have currents that have the same direction, but differing magnitude. The current in wire A is I, and the current in wire B is 2I. Which one of the following statements concerning the situation is true? A) Both wires attract each other with the same force...

29. I Restricted three body problem (numerical simulation of gravitational attraction)

Hello! I am implementing the three body restricted problem numerically (2 of them are massive and the 3rd one is not affecting them, so it is just moving in the potential created by them). I implemented it and if I put the 3rd one close to one of the big ones it moves in circles around it, while...
30. Force of magnetic attraction between hemispheres

Homework Statement Calculate the force of magnetic attraction between the northern and southern hemispheres of a uniformly charged spinning spherical shell, with radius R, angular velocity ω and surface charge density σ. Homework Equations Maxwell Tensor : Tm = [/B](1/μ) * ((B*n)B -...
31. R

B Pauli's exclusion principle

So my question is why can't 2 object be at the exact same potion, (i.e. overlap). Why can't a +ve quark and electron just merge. In an universe where there is no force caused due to charge, why can't we just walk through a solid wall.
32. E

Attraction of a positive and negative charge

No one could ever explain to me the mechanism how attraction of positive and negative charge works. Can you? (Exchange of (virtual) photons only explains repulsion.) An electrical field is playing hide and seek.
33. R

How do you calculate the Force of Attraction of two magnets?

I just took physics 2. We learned how to calculate the force of a magnetic field on a current or moving charges. What we didn't learn is how to calculate the force of attraction of two bar magnets or electromagnets for that matter. I'm building a coilgun and having a set of equations for this...
34. B Gravitational force between two objects?

I know that the force of gravity is (ma)=GMm/r^2 or a=GM/r^2 This makes sense and If I were to drop a bowling ball down to Earth I'd expect it to fall with 9.8m/s^2. However I can calculate that the bowling ball has its own gravity using the formula noted above. My question is what will be the...

We know a magnet has field with direction from North to South. Why when a piece of iron come close to the magnet can either be attracted and from both sites and not for example from one pole?
36. Dipole-Dipole Attraction in Molecules: Analysis of BCl3, XeF4, AsH3, and SCl3

Homework Statement http://i.imgur.com/8pFdEDX.png Homework Equations polarity of the element The Attempt at a Solution BCl3 is a trigonal planar which the forces would be balanced. Thus it is a neutral substance. XeF4 is with tetrahedral shape where one side is a lone pair, which the charge...
37. Why do maglev trains use attraction vs repulsion

I'm trying to find out why EMS maglev trains use magnetic attraction instead of repulsion. Given that the attractive force diminishes with distance it seems the forces would have to match exactly or else one of the two forces would win out and the train would come to a grinding halt. But with...
38. I Relativity, magnetic attraction, and comoving electrons....

How can relativity explain the magnetic attraction of two electrons (or two electron beams) comoving in a vacuum at some certain constant velocity? It is well known (https://acceleratorinstitute.web.cern.ch/acceleratorinstitute/ACINST89/Schindl_Space_Charge.pdf) that two parallel electrons or...
39. Metal: no attraction to magnet and block magnetic fields?

Hi, Can anyone help me in finding out a Diamagnetic or Paramagnetism or Ferromagnetism or any other metal which has following capabilities: 1- Should not be attractive towards magnet. 2- Should not allow magnetic fields to pass through inside. Thanks! THG
40. Electrostatic polarization and paper bits attraction

Hello, I have been reflecting over this for the past few days. We can charge two insulators by rubbing them against each other. The two materials end up having an equal amount of opposite charge. For example, a glass rod rubbed with silk will become positively charged and the silk negatively...
41. Interesting experiment about the attraction between two magnets

We know that the attractive force between the opposing poles of identical permanent magnets is a product of their field strength and that the total force diminishes as the distance between them increases. If we assumed the magnets to be point entities, the formulation is the same as that for...

say i were standing next to something very massive, like a battleship in drydock, and i were to hold a feather (not massive) very close to it. Would i witness any gravitational attraction between the feather and the ship? If not, why not? What if i did the same with a single filament of spider...
43. Magnetic Attraction: Is Bar Magnet Symmetrical?

If I have a bar magnet is it correct to assume that the bar is symmetrically magnetic? In other words is one pole just as likely to attract as the other end? Here's where I'm going with this. A compass needle lines up north and south. Is this because one end is attracted to north AND the...
44. I Relativistic Effect on Attraction between Moving Masses?

Magnetism has be explained as a relativistic effect of moving charges. This was something we were shown in undergrad. Is there a similar effect when masses move relative to each other? 1. Is there any difference between the gravitational force between a single massive particle and a very...
45. Find the force of attraction for a particle outside sphere

Homework Statement A sphere of radius R contains two spherical cavities. Each cavity has a radius of R/2 and touches both the outside surface of the sphere and its center as shown. The mass of a similar sphere without the cavities is M. Find the force of attraction on a small particle of mass m...
46. How to calculate velocity from the attraction of two charges

I need to calculate the acceleration of an proton to a metal plate with a charge of 16 Coulombs(negative charge), 1 meter away. Then I need to calculate the velocity at the moment it passes the plate. Starting Velocity is 0 m/s. What is the velocity and what is the acceleration? This is not...
47. Is sexual attraction necessary for romantic love?

From an evolutionary standpoint, humans evolved to have the ability and tendency to fall in romantic love because combination of DNA (via sex) served a huge advantage in propagation of genes, and because of the enormous time it takes to successfully raise an organism until it fully developed a...
48. Question about Gravity and Elecromagnetism and Attraction

I am kind of an arm chair layman, The following is just my own curious mind working furiously on something I know I don't completely understand, and yet want to. It seems to me that just about every piece of matter is made up of mass, and therefor has some level of electromagnetic and gravitic...
49. B Does gravitational time dilation cause gravity's attraction?

Physics Videos by Eugene Khutoryansky (a widely respected channel) recently posted a video on YouTube suggesting this. I know that gravitational fields cause time dilation (with time passing more slowly the closer an object is to the centre of gravity, relative to more distant observers), but...
50. B Gravitational attraction between two masses

hi I'm writing a javascript application to illustrate gravitational attraction between masses, but am getting hung up on some of the details, particularly mow far masses move in response to each other's gravitation. I've read all available wikipedia articles on gravity and have come up with...