![Electric Charge](http://s1.studyres.com/store/data/004989338_1-218843c1026d04fba84be60f097463e7-300x300.png)
Electric Charge
... • Explain forces in terms of electric fields. • Determine energies from electric potential. ...
... • Explain forces in terms of electric fields. • Determine energies from electric potential. ...
Figure 2.4 shows the unusual path of a confused football player. He
... The minimum possible value for x will be exactly equal to d when the two dipoles are touching. Even in this case, the quantity (3x2 – d2) will be positive. For all values of x and d, therefore, the numerator will be positive and the net force on the left dipole will be to the right. A similar analys ...
... The minimum possible value for x will be exactly equal to d when the two dipoles are touching. Even in this case, the quantity (3x2 – d2) will be positive. For all values of x and d, therefore, the numerator will be positive and the net force on the left dipole will be to the right. A similar analys ...
Nucleus Chapt 4
... Hofstadter thought big. He had to, because the laws of physics demanded that large machines – what we might call ‘mega-microscopes’ – are needed to produce electrons with high enough energies to penetrate the secrets of the nucleus. To understand how it is possible to gain an idea of the size of nuc ...
... Hofstadter thought big. He had to, because the laws of physics demanded that large machines – what we might call ‘mega-microscopes’ – are needed to produce electrons with high enough energies to penetrate the secrets of the nucleus. To understand how it is possible to gain an idea of the size of nuc ...
Document
... the first car’s velocity will increase in magnitude but not change direction. the first car’s velocity will gradually change direction more and more toward that of the force while increasing in magnitude. the first car’s velocity will gradually change direction more and more toward that of the force ...
... the first car’s velocity will increase in magnitude but not change direction. the first car’s velocity will gradually change direction more and more toward that of the force while increasing in magnitude. the first car’s velocity will gradually change direction more and more toward that of the force ...
FORCES and MOTIO BENCHMARK REVIEW Section 5
... On a roller coaster, PE is greatest at the top of the hill, but KE is greatest at the bottom of the hill. Because of friction, some energy is always converted into thermal energy during an energy conversion. Thermal energy is wasteful energy because it is not used to do work. A closed system is a gr ...
... On a roller coaster, PE is greatest at the top of the hill, but KE is greatest at the bottom of the hill. Because of friction, some energy is always converted into thermal energy during an energy conversion. Thermal energy is wasteful energy because it is not used to do work. A closed system is a gr ...
PH504lec1011-3
... between two configurations is given by the work done by external forces to change the system from one configuration to the other (this is done infinitesimally slowly so that there is no change in the kinetic energy). If U is positive then the new configuration has a greater potential energy than th ...
... between two configurations is given by the work done by external forces to change the system from one configuration to the other (this is done infinitesimally slowly so that there is no change in the kinetic energy). If U is positive then the new configuration has a greater potential energy than th ...
Nuclear force
![](https://commons.wikimedia.org/wiki/Special:FilePath/ReidForce2.jpg?width=300)
The nuclear force (or nucleon–nucleon interaction or residual strong force) is the force between protons and neutrons, subatomic particles that are collectively called nucleons. The nuclear force is responsible for binding protons and neutrons into atomic nuclei. Neutrons and protons are affected by the nuclear force almost identically. Since protons have charge +1 e, they experience a Coulomb repulsion that tends to push them apart, but at short range the nuclear force is sufficiently attractive as to overcome the electromagnetic repulsive force. The mass of a nucleus is less than the sum total of the individual masses of the protons and neutrons which form it. The difference in mass between bound and unbound nucleons is known as the mass defect. Energy is released when nuclei break apart, and it is this energy that used in nuclear power and nuclear weapons.The nuclear force is powerfully attractive between nucleons at distances of about 1 femtometer (fm, or 1.0 × 10−15 metres) between their centers, but rapidly decreases to insignificance at distances beyond about 2.5 fm. At distances less than 0.7 fm, the nuclear force becomes repulsive. This repulsive component is responsible for the physical size of nuclei, since the nucleons can come no closer than the force allows. By comparison, the size of an atom, measured in angstroms (Å, or 1.0 × 10−10 m), is five orders of magnitude larger. The nuclear force is not simple, however, since it depends on the nucleon spins, has a tensor component, and may depend on the relative momentum of the nucleons.A quantitative description of the nuclear force relies on partially empirical equations that model the internucleon potential energies, or potentials. (Generally, forces within a system of particles can be more simply modeled by describing the system's potential energy; the negative gradient of a potential is equal to the vector force.) The constants for the equations are phenomenological, that is, determined by fitting the equations to experimental data. The internucleon potentials attempt to describe the properties of nucleon–nucleon interaction. Once determined, any given potential can be used in, e.g., the Schrödinger equation to determine the quantum mechanical properties of the nucleon system.The discovery of the neutron in 1932 revealed that atomic nuclei were made of protons and neutrons, held together by an attractive force. By 1935 the nuclear force was conceived to be transmitted by particles called mesons. This theoretical development included a description of the Yukawa potential, an early example of a nuclear potential. Mesons, predicted by theory, were discovered experimentally in 1947. By the 1970s, the quark model had been developed, which showed that the mesons and nucleons were composed of quarks and gluons. By this new model, the nuclear force, resulting from the exchange of mesons between neighboring nucleons, is a residual effect of the strong force.