X1

X1 consists of educational physics articles in Persian. To see the (English) abstract of each article, no particular software is needed. But the full texts are in the pdf format. To view them, Adobe (Acrobat) reader 5 or later is needed. Adobe reader can be obtained from Adobe reader download.

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X1-192 (2025/11/03) abs      full text
                    The harmonic oscillator, with friction and noise II

X1-191 (2025/10/04) abs      full text
                    The harmonic oscillator, with friction and noise I

X1-190 (2025/08/03) abs      full text
                    The second law of thermodynamics

X1-189 (2025/07/03) abs      full text
                    The linear fitting, the ellipsoid

X1-188 (2025/05/03) abs      full text
                    Two dimensional evolution, and Hamiltonian

X1-187 (2025/04/03) abs      full text
                    The electrostatic force: symmetry and the charge

X1-186 (2025/02/03) abs      full text
                    An ideal solenoid, which is not infinitely-long

X1-185 (2025/01/03) abs      full text
                    Conducting sphere in uniform field: the force

X1-184 (2024/11/03) abs      full text
                    Completeness, and bound states

X1-183 (2024/10/03) abs      full text
                    Kepler's problem and parabolic coordinates, quantum

X1-182 (2024/08/03) abs      full text
                    Kepler's problem and parabolic coordinates, classical

X1-181 (2024/07/03) abs      full text
                    The magnetohydrodynamic waves

X1-180 (2024/05/03) abs      full text
                    Dirichlet Green's function on a ribbon

X1-179 (2024/04/01) abs      full text
                    Solids at low temperatures: pressure, heat-capacity, and bulk-modulus

X1-178 (2024/02/12) abs      full text
                    The magnetic multipoles, and enumeration

X1-177 (2024/01/20) abs      full text
                    The electric multipoles, and enumeration

X1-176 (2023/11/23) abs      full text
                    The mean field, and the extremum of the free energy

X1-175 (2023/10/19) abs      full text
                    Statistical mechanics with velocity source

X1-174 (2023/08/02) abs      full text
                    The Fokker-Planck equation II

X1-173 (2023/07/12) abs      full text
                    The Fokker-Planck equation I

X1-172 (2023/05/16) abs      full text
                    The edge effect

X1-171 (2023/04/19) abs      full text
                    Estimation of the variance and its uncertainty

X1-170 (2023/02/20) abs      full text
                    The magnetic field and the force for a current-carrying circular torus

X1-169 (2023/01/26) abs      full text
                    The magnetic field and the force for a current-carrying circular cylinder

X1-168 (2022/11/23) abs      full text
                    Radiation from a circular cylinder with axial current

X1-167 (2022/10/20) abs      full text
                    Radiation from a circular cylinder with azimuthal current

X1-166 (2022/08/24) abs      full text
                    Measurement of the probability, with finite population

X1-165 (2022/07/22) abs      full text
                    The Poisson equation in a column

X1-164 (2022/05/19) abs      full text
                    Evaporation of a mixture

X1-163 (2022/04/14) abs      full text
                    The Poisson equation on the sphere

X1-162 (2022/02/19) abs      full text
                    Kinetics of relativistic ideal gases II

X1-161 (2022/01/20) abs      full text
                    The capacitance, two dimensions

X1-160 (2021/11/26) abs      full text
                    Kinetics of relativistic ideal gases I

X1-159 (2021/10/22) abs      full text
                    Newton's third law, in not-necessarily-linear spaces

X1-158 (2021/08/27) abs      full text
                    The electromagnetic field, the Lagrangian and the Hamiltonian

X1-157 (2021/07/22) abs      full text
                    The probability density, and the generating function III

X1-156 (2021/05/28) abs      full text
                    The probability density, and the generating function II

X1-155 (2021/04/24) abs      full text
                    The probability density, and the generating function I

X1-154 (2021/02/19) abs      full text
                    Relativistic quantization, in terms of non-relativistic quantization

X1-153 (2021/01/27) abs      full text
                    Mean free time, mean free path

X1-152 (2020/11/21) abs      full text
                    Relativistic reactions with three emerging particles

X1-151 (2020/10/29) abs      full text
                    Relativistic reactions with two emerging particles

X1-150 (2020/08/26) abs      full text
                    Nonlinear oscillations, perturbation, renormalization II

X1-149 (2020/07/25) abs      full text
                    Nonlinear oscillations, perturbation, renormalization I

X1-148 (2020/05/27) abs      full text
                    The static friction and the kinetic friction, stability

X1-147 (2020/04/15) abs      full text
                    Wave propagation, and the time-idependent source

X1-146 (2020/02/21) abs      full text
                    The propagator and quadratic actions

X1-145 (2020/01/28) abs      full text
                    The precession of the earth's axis due to the moon and the sun

X1-144 (2019/11/21) abs      full text
                    Potential inside a rectangle

X1-143 (2019/10/21) abs      full text
                    The Dirichlet problem for the disc, using the conformal transformation

X1-142 (2019/08/12) abs      full text
                    Uncertainty in practical measurement of probability

X1-141 (2019/07/27) abs      full text
                    A structured relativistic particle

X1-140 (2019/05/23) abs      full text
                    A charged particle in the magnetic and electric fields of a long wire, relativistic

X1-139 (2019/04/12) abs      full text
                    A charged particle in the magnetic and electric fields of a long wire

X1-138 (2019/02/21) abs      full text
                    A charged particle in the electric field of a long wire

X1-137 (2019/01/22) abs      full text
                    A charged particle in the magnetic field of a long wire

X1-136 (2018/11/28) abs      full text
                    Quantum mechanics on the circle

X1-135 (2018/10/19) abs      full text
                    The electric fields of the half-line and the half-plane

X1-134 (2018/08/29) abs      full text
                    The motion of a projectile with linear drag

X1-133 (2018/07/24) abs      full text
                    The field of a superluminal charged particle

X1-132 (2018/05/30) abs      full text
                    Motion of the boundary between two phases

X1-131 (2018/04/26) abs      full text
                    Discrete translation symmetry

X1-130 (2018/02/25) abs      full text
                    The frequency of the vertical motion of a floating body

X1-129 (2018/01/26) abs      full text
                    The inverse problem for the central force

X1-128 (2017/11/27) abs      full text
                    Gauge fixing, and the BRST transformation

X1-127 (2017/10/27) abs      full text
                    Nonholonomic equality-constraints and their work

X1-126 (2017/08/21) abs      full text
                    The force and energy for a set of conductors

X1-125 (2017/07/27) abs      full text
                    The crystal and the potential

X1-124 (2017/05/27) abs      full text
                    The path of the sun in the sky

X1-123 (2017/04/07) abs      full text
                    The central force and special relativity

X1-122 (2017/02/25) abs      full text
                    The field-lines of a charge which moves on a straight line

X1-121 (2017/01/27) abs      full text
                    The paradox of the drift velocity in matter

X1-120 (2016/11/27) abs      full text
                    The Galileo symmetry

X1-119 (2016/10/29) abs      full text
                    The energy-momentum tensor III

X1-118 (2016/08/27) abs      full text
                    The electric force on concentrated sources

X1-117 (2016/07/28) abs      full text
                    Spinors and the curved space

X1-116 (2016/05/26) abs      full text
                    The oblateness of the earth, the latitude, and the arc length

X1-115 (2016/04/29) abs      full text
                    The maximally-symmetric spaces

X1-114 (2016/02/25) abs      full text
                    The Frenet frame

X1-113 (2016/01/28) abs      full text
                    The curvature, the volume, the area

X1-112 (2015/11/29) abs      full text
                    Two port circuits

X1-111 (2015/10/30) abs      full text
                    Approximate action for the interaction of charged particles

X1-110 (2015/08/28) abs      full text
                    Fitting, estimation, uncertainty II

X1-109 (2015/07/30) abs      full text
                    Fitting, estimation, uncertainty I

X1-108 (2015/05/29) abs      full text
                    A finite conducting rod

X1-107 (2015/04/30) abs      full text
                    Angle-preserving and area-preserving planar maps of the sphere

X1-106 (2015/02/20) abs      full text
                    The stationary shape of the surface of a moving fluid

X1-105 (2015/01/24) abs      full text
                    The Green's function of the Laplacian for the space outside a disc

X1-104 (2014/11/28) abs      full text
                    Equilibrium of ordinary stars

X1-103 (2014/10/30) abs      full text
                    Scattering in one dimension II

X1-102 (2014/08/22) abs      full text
                    Degenerate perturbation

X1-101 (2014/07/25) abs      full text
                    Estimating the mass and radius of degenerate stars

X1-100 (2014/05/30) abs      full text
                    The geometry of emission and absorbtion of radiation

X1-099 (2014/04/25) abs      full text
                    Measurement, estimation, uncertainty

X1-098 (2014/02/22) abs      full text
                    A falling liquid

X1-097 (2014/01/31) abs      full text
                    Dipole density

X1-096 (2013/11/29) abs      full text
                    Stability of the atmosphere, and the height-dependence of the temperature

X1-095 (2013/10/30) abs      full text
                    Mappings defined on SU(2) and SO(3)

X1-094 (2013/08/31) abs      full text
                    The manifolds of the groups SU(2) and SO(3)

X1-093 (2013/07/28) abs      full text
                    The image of a charge distribution

X1-092 (2013/05/29) abs      full text
                    Time-dependent perturbation, eigenvalue shift, and survival

X1-091 (2013/04/25) abs      full text
                    A relativistic particle in external fields

X1-090 (2013/02/26) abs      full text
                    Motion of a spherically-symmetric ball on a plane

X1-089 (2013/01/28) abs      full text
                    Measurement of the probability

X1-088 (2012/11/29) abs      full text
                    Symmetries of the nonrelativistic spacetime, 
                    as a contraction of symmetries of the relativistic spacetime

X1-087 (2012/10/29) abs      full text
                    A cable which is hanging upwards from the earth

X1-086 (2012/08/30) abs      full text
                    The geometry and dynamics of surfaces embedded in space

X1-085 (2012/07/31) abs      full text
                    Axis symmetry in arbitrary dimesnion

X1-084 (2012/05/26) abs      full text
                    Boosted circuits

X1-083 (2012/04/27) abs      full text
                    The polarization and the phase of light

X1-082 (2012/02/28) abs      full text
                    The magnetic field of a thin solenoid

X1-081 (2012/01/19) abs      full text
                    Transverse-electric and transverse-magnetic fields

X1-080 (2011/11/28) abs      full text
                    Strain, Stress, and moduli

X1-079 (2011/10/28) abs      full text
                    Distribution of charge between two conducting spheres tangent to each other

X1-078 (2011/08/25) abs      full text
                    Gaussian optics and the transfer matrix

X1-077 (2011/07/28) abs      full text
                    Analemma

X1-076 (2011/05/25) abs      full text
                    Adiabatic invariants, and the pendulum's energy

X1-075 (2011/04/29) abs      full text
                    The perihelion of the Earth in the orbit of the Sun

X1-074 (2011/02/23) abs      full text
                    The potential in some problems with nonlocalized sources

X1-073 (2011/01/25) abs      full text
                    Time as a dynamical variable

X1-072 (2010/11/26) abs      full text
                    Eigenexponents of passive circuits

X1-071 (2010/10/21) abs      full text
                    A relativistic particle in a scalar field

X1-070 (2010/08/20) abs      full text
                    Wave propagation in discrete space

X1-069 (2010/07/28) abs      full text
                    The generator of translation in the box

X1-068 (2010/05/27) abs      full text
                    The conformal transformation and the Poisson's problem in two dimensions

X1-067 (2010/04/24) abs      full text
                    Simultaneous observers

X1-066 (2010/02/26) abs      full text
                    Two charged conductiong spheres

X1-065 (2010/01/28) abs      full text
                    The scalar potential of a tube with an azimuthal current

X1-064 (2009/11/28) abs      full text
                    Poincaré mappings and the principles of special relativity   

X1-063 (2009/10/29) abs      full text
                    The internal energy of a relativistic ideal gas   

X1-062 (2009/08/19) abs      full text
                    Diagrammatics I

X1-061 (2009/07/30) abs      full text
                    The de Hass-van Alphen effect in two dimensions

X1-060 (2009/05/22) abs      full text
                    Virial and the van der Waals equation

X1-059 (2009/04/24) abs      full text
                    Parallel transport in two dimensions

X1-058 (2009/02/26) abs      full text
                    The statistical mechanics of the rotator

X1-057 (2009/01/08) abs      full text
                    Thermodynamics of single particle interactions

X1-056 (2008/11/28) abs      full text
                    The semiclassical approximation

X1-055 (2008/10/25) abs      full text
                    The dispersion relation of vector waves

X1-054 (2008/08/27) abs      full text
                    Planets' lights

X1-053 (2008/07/25) abs      full text
                    Rolling friction

X1-052 (2008/05/29) abs      full text
                    Surface waves of liquids

X1-051 (2008/04/29) abs      full text
                    Thomas precession

X1-050 (2008/02/29) abs      full text
                    Relativity and constant acceleration

X1-049 (2008/01/31) abs      full text
                    Relativity and systems with variable mass

X1-048 (2007/11/23) abs      full text
                    Wave propagation in moving media

X1-047 (2007/09/13) abs      full text
                    The action and discrete time

X1-046 (2007/07/31) abs      full text
                    Distillation and the composition of liquid and vapor

X1-045 (2007/06/29) abs      full text
                    The triple point, and the vapour pressure

X1-044 (2007/04/19) abs      full text
                    The Sagnac effect

X1-043 (2007/02/28) abs      full text
                    The holomorphic picture of the harmonic oscillator

X1-042 (2007/01/29) abs      full text
                    Evolution of continuous random variables

X1-041 (2006/11/17) abs      full text
                    A long cylinder floating on the surface of a liquid

X1-040 (2006/09/29) abs      full text
                    The rotational states and the phase space

X1-039 (2006/07/31) abs      full text
                    Towards a specific point on the sphere

X1-038 (2006/06/29) abs      full text
                    Rigid body and special relativity

X1-037 (2006/04/27) abs      full text
                    Space symmetries of the magnetic field

X1-036 (2006/02/12) abs      full text
                    The time interval between two successive Moonsets

X1-035 (2006/01/08) abs      full text
                    Uniformly-charged solid ellipsoid

X1-034 (2005/11/08) abs      full text
                    The spinor representations of so(4)

X1-033 (2005/09/03) abs      full text
                    Escape of a gas through a small opening

X1-032 (2005/07/30) abs      full text
                    Motion of a charge in a uniform and constant electromagnetic field

X1-031 (2005/06/30) abs      full text
                    The sound barrier

X1-030 (2005/04/12) abs      full text
                    The density matrix

X1-029 (2005/02/20) abs      full text
                    The energy-momentum tensor II

X1-028 (2005/01/07) abs      full text
                    The energy-momentum tensor I                    

X1-027 (2004/10/23) abs      full text
                    The area distribution of a submanifold

X1-026 (2004/09/13) abs      full text
                    Why do stars twinkle?

X1-025 (2004/07/23) abs      full text
                    Newton's laws

X1-024 (2004/06/12) abs      full text
                    Newtonian cosmology                    

X1-023 (2004/04/01) abs      full text
                    Scattering in one dimension I                   

X1-022 (2004/02/21) abs      full text
                    Hydrogen-like ions, and spherical spinors                    

X1-021 (2004/01/22) abs      full text
                    The electromagnetic field equations in matter                    

X1-020 (2003/11/20) abs      full text
                    The pressure-difference due to the surface tension, 
                    and the differential geometry of surfaces                    

X1-019 (2003/09/29) abs      full text
                    The motion of a charged particle 
                    in an almost-homogeneous magnetic field

X1-018 (2003/08/28) abs      full text
                    The effect of the Earth's atmosphere 
                    on the apparent size and shape of objects

X1-017 (2003/06/08) abs      full text
                    Symmetry and the small oscillations

X1-016 (2003/05/12) abs      full text
                    Symmetry and the Lagrangian formulation II

X1-015 (2003/03/21) abs      full text
                    Symmetry and the Lagrangian formulation I

X1-014 (2003/02/12) abs      full text
                    A bubble between two circular boundaries:
                    a simple phase transition

X1-013 (2002/12/08) abs      full text
                    Rigid body rotation, 
                    and the phase space formulation

X1-012 (2002/10/04) abs      full text
                    Magnetic multipoles in magnetostatics

X1-011 (2002/09/01) abs      full text
                    Birth of the modern quantum mechanics, 
                    in today's language

X1-010 (2002/07/14) abs      full text
                    Elliptic coordinates 
                    in some electromagnetics problems

X1-009 (2002/05/09) abs      full text
                    Oscillations of a body attached to 
                    a massive spring

X1-008 (2002/03/21) abs      full text
                    How oblate is the Earth?

X1-007 (2002/01/30) abs      full text
                    Transverse oscillations of a column of liquid

X1-006 (2001/12/21) abs      full text
                    Stochastic processes

X1-005 (2001/10/03) abs      full text
                    The electrostatic potential,
                    the potential-coefficients matrix,
                    and the capacity matrix

X1-004 (2001/08/01) abs      full text
                    Sundial

X1-003 (2001/06/28) abs      full text
                    Green's functions of the Poisson and
                    diffusion equation on the sphere
                    and plane: contraction

X1-002 (2001/04/01) abs      full text
                    Green's functions of the wave equation
                    in different dimensions

X1-001 (2001/02/21) abs      full text
                    Symmetries in quantum mechanics,
                    and the degeneracy of the Hamiltonian