discovery of protons
1) which scientist discovered
2) discovery
3) experiment
4) conclusion
Answers
Answer:
A proton is a subatomic particle, symbol
p
or
p+
, with a positive electric charge of +1e elementary charge and a mass slightly less than that of a neutron. Protons and neutrons, each with masses of approximately one atomic mass unit, are collectively referred to as "nucleons" (particles present in atomic nuclei).
Proton
Quark structure proton.svg
The quark content of a proton. The color assignment of individual quarks is arbitrary, but all three colors must be present. Forces between quarks are mediated by gluons.
Classification
Baryon
Composition
2 up quarks (u), 1 down quark (d)
Statistics
Fermionic
Interactions
Gravity, electromagnetic, weak, strong
Symbol
p
,
p+
,
N+
, 1
1H+
Antiparticle
Antiproton
Theorized
William Prout (1815)
Discovered
Observed as H+ by Eugen Goldstein (1886). Identified in other nuclei (and named) by Ernest Rutherford (1917–1920).
Mass
1.67262192369(51)×10−27 kg[1]
938.27208816(29) MeV/c2[2]
1.007276466621(53) Da[2]
Mean lifetime
> 2.1×1029 years (stable)
Electric charge
+1 e
1.602176634×10−19 C[2]
Charge radius
0.8414(19) fm[2]
Electric dipole moment
< 5.4×10−24 e⋅cm
Electric polarizability
1.20(6)×10−3 fm3
Magnetic moment
1.41060679736(60)×10−26 J⋅T−1[2]
1.52103220230(46)×10−3 μB[2]
2.79284734463(82) μN[2]
Magnetic polarizability
1.9(5)×10−4 fm3
Spin
1
/
2
Isospin
1
/
2
Parity
+1
Condensed
I(JP) =
1
/
2
(
1
/
2
+)
One or more protons are present in the nucleus of every atom; they are a necessary part of the nucleus. The number of protons in the nucleus is the defining property of an element, and is referred to as the atomic number (represented by the symbol Z). Since each element has a unique number of protons, each element has its own unique atomic number.
The word proton is Greek for "first", and this name was given to the hydrogen nucleus by Ernest Rutherford in 1920. In previous years, Rutherford had discovered that the hydrogen nucleus (known to be the lightest nucleus) could be extracted from the nuclei of nitrogen by atomic collisions.[3] Protons were therefore a candidate to be a fundamental particle, and hence a building block of nitrogen and all other heavier atomic nuclei.
Although protons were originally considered fundamental or elementary particles, in the modern Standard Model of particle physics, protons are classified as hadrons, like neutrons, the other nucleon. Protons are composite particles composed of three valence quarks: two up quarks of charge +
2
/
3
e and one down quark of charge −
1
/
3
e. The rest masses of quarks contribute only about 1% of a proton's mass.[4] The remainder of a proton's mass is due to quantum chromodynamics binding energy, which includes the kinetic energy of the quarks and the energy of the gluon fields that bind the quarks together. Because protons are not fundamental particles, they possess a measurable size; the root mean square charge radius of a proton is about 0.84–0.87 fm (or 0.84×10−15 to 0.87×10−15 m).[5][6] In 2019, two different studies, using different techniques, have found the radius of the proton to be 0.833 fm, with an uncertainty of ±0.010 fm.[7][8]
Free protons occur occasionally on Earth: thunderstorms can produce protons with energies of up to several tens of MeV.[9][10] At sufficiently low temperatures and kinetic energies, free protons will bind to electrons. However, the character of such bound protons does not change, and they remain protons. A fast proton moving through matter will slow by interactions with electrons and nuclei, until it is captured by the electron cloud of an atom. The result is a protonated atom, which is a chemical compound of hydrogen. In vacuum, when free electrons are present, a sufficiently slow proton may pick up a single free electron, becoming a neutral hydrogen atom, which is chemically a free radical. Such "free hydrogen atoms" tend to react chemically with many other types of atoms at sufficiently low energies. When free hydrogen atoms react with each other, they form neutral hydrogen molecules (H2), which are the most common molecular component of molecular clouds in interstellar space.
Free protons are routinely used for accelerators for proton therapy or various particle physics experiments, with the most powerful example being the Large Hadron Collider.
Answer:
1) proton is discovered by goldstein in 1898
2) discovery constitute of positive rays that is particle is that contain protons
3) experiment
goldstein used a modified cathode ray tube with a perforated cathode
He observed a new type of rays produced from the anode passing through the holes of the perforated cathode. These rays were called anode rays
conclusion
Anode rays consist of positively charged particles now called protons
The postive rays were affected by election & magnetic fields but in the direction opposite to that of cathode rays
Thus with the discovery of the positive particles - protons was initiated