Physical constants and data

Students, when you do physical topics,

forgot some of the physical constants,

see here.

Conversion factors

Length

    2.54cm∕in

    1.609344km/mi

    9.461×10⁵m/light-year

Mass

    1.6605×10^-27kg/u

Force

    10⁵dyn/N

Pressure

    1.01325×10 ⁵（N/m²）/atm

    1.01325×10 ⁵bar/atm

    1.01325×10³Hbar/atm

    76cmHg/atm

    1torr/mmHg

Work and energy

    10⁷ergs/J

    4.184J/cal

    3.60×10⁶J/kWh

    1.054J/Btu

    1.6022×10^-19J/eV

    6.242×10¹⁸eV/J

    0.239cal/J

Power

    746W/hp  

Electrical

    1.6022C/electron

    96,487C/faraday

Physical constants and data

Speed of light

       C＝2.997925×10⁸m/s

Gravitational constant

      G＝6.67×10^-11N˙m²/kg²

Avogadro's number   

     N_A＝6.022×10²³particles/mole

    N_A＝6.022×10²⁶particles/kg.atom

Boltzmann's constant

    κ＝1.3806×10^-23J/K  ，κ≡R/N_A

gas constant

     R＝8314J/kg˙mole˙K

Planck's contant

     h＝6.6262×10^-34J˙s

electron charge

     e＝1.60219×10^-19C/charge

electron rest mass

     m_e＝9.1096×10^-31kg

          ＝5.4859×10^-4u

Proton rest mass

     m_p＝1.67261×10^-27kg

          ＝1.0072766u

Neutron rest mass

     m_n＝1.67492×10^-27kg

          ＝1.0086652u

Permittivity constant

    ε_o＝8.85419×10^-12C²/N˙m²

permeability constant

    μ_o＝4π×10^-7N/A²

standard gravitational acceleration

      g＝9.80665m/s²

mass of earth                    8.98×10²⁴kg

avg radius of earth           6.37×10⁶m

avg density of earth                5.57g/cm³

avg earth-moon distance      3.84×10⁸m

avg earth-sun distance          1.496×10¹¹m

mass of sun                               1.99×10³⁰kg

radium of sun                           7×10⁸m

Sun^，s  radiation intensity at the earth

                                                      0.032cal/cm²˙s

                                                      0.134J/cm²˙s

Quantum theory formula

   E＝hν

   p＝hν/c＝h/λ

Photoelectric equation

  hν＝（1/2）mv²＋eφ

  eφ：Work function

Obviously， eφ＝hν_o   ν_o：Lower limit frequency
    eV_s＝（1/2）mv²

  V_s： Cut-off voltage

Matter wave formula
   ν＝E/h
   λ＝h/p

SERIES EXPENSIONS 

     （丨x丨＜1 unless otherwise indicated）

    （1±x）ⁿ＝1 ± nx＋（n）（n﹣1）/_2!x²±…

    （1＋x）^-n＝1 ﹣nx＋n（n﹣1）/_2!x²﹣…

    （1﹣x）^-n＝1＋nx＋n（n﹣1）/_2!x²＋…

    （1±x）^½＝1 ± ½x ＋ ¹/₈x² ± ¹/₁₆x³ ﹣…

    （1＋x）^-½＝1﹣½x＋³/₈x²﹣⁵/₁₆x³＋…

    （1﹣x）^-½＝1＋½x＋³/₈x²＋⁵/₁₆x³＋…

Scientific notation   a×10ⁿ  ,   1≦a＜10,      n   I
The following formulas for all real
     sinx＝x﹣x³/_3!＋x⁵/_5!﹣…

    cosx＝1﹣x²/_2!＋x⁴/_4!﹣…

      e^x＝1＋x＋x²/_2! ＋x³/_3! ＋…

      x  1，        e^x ≒ 1＋x

    

  ㏑（1±x）＝±x﹣½x²±¹/₃x³﹣¼x⁴±… 

Mozart's music for children

(Музыка Моцарта для детей)

                                                                   

                                                                  

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