What is proton state its characteristics?

A proton, symbol p or p+, is one of the subatomic particles that make up matter. In the universe, protons are abundant, making up about half of all visible matter. It has a positive electric charge (+1e) and a rest mass equal to 1.67262 × 10−27 kg (938.272 MeV/c2)— marginally lighter than that of the neutron but nearly 1836 times greater than that of the electron. The proton has a mean square radius of about 0.87 × 10−15 m or 0.87 fm, and it is a spin – ½ fermion.

protonThe protons exist in the nuclei of typical atoms, along with their neutral counterparts, the neutrons. Neutrons and protons, commonly called nucleons, are bound together in the atomic nucleus, where they account for 99.9 percent of the atom’s mass. Research in high-energy particle physics in the 20th century revealed that neither the neutron nor the proton is not the smallest building block of matter.

Structure of Proton

Protons and neutrons also have their structure. Inside the protons and neutrons, we find true elementary particles called quarks. Protons and neutrons are bound together within the nucleus through a strong force. This fundamental interaction governs the behavior of the quarks that make up the individual protons and neutrons.

The proton has a quark composition of uud, and so its charge quantum number is:

q(uud) = ⅔ + ⅔ + (-1/3) = +1

The mass of the proton is 938.272 MeV/c2, whereas the mass of the three quarks is only about 12 MeV/c2 (only about 1% of the mass-energy of the neutron). Like the proton, most of the mass (energy) of the neutron is in the form of the strong nuclear force energy (gluons). The quarks of the neutron are held together by gluons, the exchange particles for the strong nuclear force.

Noteworthy, because most of your mass is due to the protons and neutrons in your body, your mass (and therefore your weight on a bathroom scale) comes primarily from the gluons that bind the constituent quarks together rather than from the quarks themselves. Mass is primarily a measure of the energies of the quark motion and the quark-binding fields of any real object. It must be noted that gluons are inherently massless and possess energy.

Stability of Proton

The free proton (a proton not bound to nucleons or electrons) is a stable particle that has not been observed to break down spontaneously to other particles. Free protons are found naturally in many situations (e.g., they make up 90% of cosmic rays) in which energies or temperatures are high enough to separate them from electrons, for which they have some affinity.

The decay of proton is also associated with the law of conservation of baryon number. Baryon number is a generalization of nucleon number, conserved in non-relativistic nuclear reactions and decays. The law of conservation of baryon number states that:

The sum of the baryon number of all incoming particles is the same as the sum of the baryon numbers of all particles resulting from the reaction.

For example, the following reaction has never been observed:

baryon-number-example-violation

even if the incoming proton has sufficient energy and charge energy and is conserved. This reaction does not conserve the baryon number since the left side has B =+2, and the right has B =+1.

On the other hand, the following reaction (proton-antiproton pair production) does conserve B and does occur if the incoming proton has sufficient energy (the threshold energy = 5.6 GeV):

baryon-number-pair-production

As indicated, B = +2 on both sides of this equation.

From these and other reactions, the conservation of the baryon number has been established as a basic principle of physics. This principle provides the basis for the stability of the proton. Since the proton is the lightest particle among all baryons, the hypothetical products of its decay would have to be non-baryons. Thus, the decay would violate the conservation of the baryon number. It must be added some theories have suggested that protons are, in fact, unstable with a very long half-life (~1030years) and that they decay into leptons. There is currently no experimental evidence that proton decay occurs.

Antiproton

antiprotonAs was written, a particle and its antiparticle have the same mass as one another but opposite electric charge and other differences in quantum numbers. That means a proton has a positive charge while an antiproton has a negative charge, and therefore they attract each other. A collision between any particle and its antiparticle partner leads to their mutual annihilation. Since matter and antimatter carry an immense amount of energy (due to E = mc2), their mutual annihilation is associated with producing intense photons (gamma rays), neutrinos, and sometimes less-massive particle-antiparticle pairs.

Protons and Neutrons in a Nucleus

nuclear fission vs fusionNuclear stability is determined by the competition between two fundamental interactions. Protons and neutrons are attracted to each other via the residual strong force. On the other hand, protons repel each other via the electric force due to their positive charge. Therefore neutrons within the nucleus act somewhat like nuclear glue. Neutrons attract each other and protons, which helps offset the electrical repulsion between protons. There are only certain combinations of neutrons and protons which form stable nuclei. For example, the most common nuclide of the common chemical element lead (Pb) has 82 protons and 126 neutrons.

Because of the strength of the nuclear force at short distances, the nuclear binding energy (the energy required to disassemble a nucleus of an atom into its component parts) of nucleons is more than seven orders of magnitude larger than the electromagnetic energy binding electrons in atoms. Therefore, nuclear

What is proton and its characteristics?

A proton is one of three main particles that make up the atom. Protons are found in the nucleus of the atom. This is a tiny, dense region at the center of the atom. Protons have a positive electrical charge of one (+1) and a mass of 1 atomic mass unit (amu), which is about 1.67×10−27 kilograms.

What is the proton?

(PROH-ton) A small, positively charged particle of matter found in the atoms of all elements. Streams of protons generated by special equipment can be used for radiation treatment.

What is proton in Class 11?

Protons are the positively charged particles which are present in the nucleus of an atom.

What are the characteristics of proton 7th standard?

Solution : (1) Protons are positively charged particles and are denoted by the symbol . P.. <br>(2) They are present in the nucleus of an atom. <br>(3) The mass of the proton is very nearly equal to 1u which is almost equal to that of the hydrogen atom.