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Sunday 23 September 2012

Why all bodies emit electromagnetic radiation?


Q.No.19: - Why all bodies emit electromagnetic radiation?
Ans: - Because of thermal motion of their molecules all bodies emit radiation called thermal radiation. Molecules are often neutral but their constituent particles like electron and protons are charged particles when molecules vibrate their atoms as a whole move and result in thermal radiation.

What are the fundamental source of electromagnetic radiation?


Q.No.18: - What are the fundamental source of electromagnetic radiation?
Ans: - Electric charges in accelerated motion are the source of electromagnetic radiation

What is the difference between proton and Δ+ particle?


Q.No.17: - What is the difference between proton and Δ+ particle?
Ans: - Proton and Δ+ particles have same quark configuration. But there is only difference of spin of quark e.g;


What is the internal structure of proton and neutron. Also show their charge by using quark charges.


Q.No.16: - What is the internal structure of proton and neutron. Also show their charge by using quark charges.
Ans: -  
 Proton           P(uud) = 2/3 + 2/3 – 1/3 = +1
 Neutron        N(ddu) = -1/3 – 1/3 + 2/3 =0

Friday 21 September 2012

What is the numerical value of charge energy and spin of up and down quark.


 Q.No.15: - What is the numerical value of charge energy and spin of up and down quark.
Ans: - For up quark
Spin    =    1/2    ;   charge     = +2/3    energy (Mc² in MeV) ≈ 4 MeV
For down quark
Spin    =    1/2    ;   charge     = -1/3     energy (Mc² in MeV) ≈ 5 MeV

How γ-rays emit from nuclei?


Q.No.14: - How γ-rays emit from nuclei?
Ans: - In the case of proton, as it is hit with ever higher energies, its quarks are elevated to higher levels, and short-lived resonances are seen. This energy is rapidly released by emitting photons. The excited levels are short lived and excess energy, typically by radiating energy in the form of gamma-ray photons, and fall back to the ground state (proton or neutron).

What is the value of neutron magnetic moment?

Q.No.13: - What is the value of neutron magnetic moment?
Ans: - The z-component of spin magnetic moment is


                           

Saturday 8 September 2012

As neutron is charge less particle then its magnetic moment well be zero or not?


Q.No.12: - As neutron is charge less particle then its magnetic moment will be zero or not?
Ans: - Although the electric charges of the quarks that form a neutron add up to zero but their individual magnetism does not cancel out which leads to the magnetic moment of neutron.

Which thing specifies the size of neutrons, protons and atom?


Q.No.11: - Which thing specifies the size of neutrons, protons and atom?
Ans: - It is the motion of these quarks that gives size of proton and neutron. The motion of electron determines the size of atoms.

In nucleons which particle is more massive and why?


Q.No.10: - In nucleons which particle is more massive and why?
Ans: - Neutron is more massive than proton because down quark is more massive than up quark and neutron contain 2 down quark and 1 up quark while in proton 1 down and 2 up quarks.

What are the mediators (field particles) of the basic forces?


Q.No.9: - What are the mediators (field particles) of the basic forces?
 Ans: - Photon of Electromagnetic force; Graviton of gravitational force; gluon of strong force; and  of weak force.
   

Enlist the fundamental four forces.


Q.No.8: - Enlist the fundamental four forces.
Ans: - (1) Electromagnetic force (2) Gravitational force (3) Weak force (4) Strong Force



How can you distinguish between delta plus and proton as they both made up of to up quark and one down quark?


 Q.No.7: - How can you distinguish between delta plus  and proton as they both made up of two up quark and one down quark?
Ans: - For Delta plus all the three quarks are of same spin but for proton spin of one of three quarks is down and the remaining two have up spin. e.g.


Using the charges of up and down quark show that proton has +1 charge and neutron is neutral particle.

Q.No.6: - Using the charges of up and down quark show that proton has +1 charge and neutron is neutral particle.
Ans: - For proton p (uud) =2/3+2/3-1/3=+1
           For Neutron n (ddu) = -1/3-1/3+2/3=0



By which symmetry the up and down quark are present in the proton and neutron?


Q.No.5: - By which symmetry the up and down quark are present in the proton and neutron?
Ans: - For Proton p(uud) and for neutron n(ddu).

Q.No.4: - What is the spin of up and down quark?


Q.No.4: - What is the spin of up and down quark?  
Ans: - Both have spin ½.

What are the energies of up and down quark?

Q.No.3: - What are the energies of up and down quark?
Ans: - The up has 4MeV and down has 5MeV energy.

What is the charge of up and down quark?

Q.No.2: - What is the charge of up and down quark?
Ans: - The charge of up quark is +2/3 and down is -1/3 respectively.

By which quarks the proton and neutrons formed?

Q.No.1: - By which quarks the proton and neutrons are formed?
Ans: - The Proton and Neutrons are formed by up and Down quarks.