## Sunday, 13 September 2015

Physical constants:-

1. Mass of an electron (Me) = 9.1x10-31kg.

2. Mass of a proton ( Mp) = 1.6725 x 10-27kg.

3. Mass of a neutron (Mn) = 1.6746 x 10-27kg.

4. Charge of an electron (e) =-1.6 x 10-19c

5. Speed of light in vacuum (c) = 3 x108 m/sec.

6. Planck Constant (h) = 6.6256 x 10-34 J x sec .

7. Universal Gravitation constant (G) = 6.67 x 10-11 Nm2/ kg2.

8. Avogadro Number (NA) = 6.023 x1023mol-1.

9. Boltzmann constant (K) = 1.38 x 10-23 J/K

10.Stefan Constant (σ) = 5.67 x 10-8 W m-2 K-4.

11.Wien Displacement Constant (b) = 2.898 x10-3m K

12.Solar Constant (S) = 1.388 x 103 W m-2

13.Mass of the sun (MS) = 2x 1030kg.

14.Mass of the earth (ME) = 5.98x 1024kg

15.Radius of the earth (Re) = 6400 Km. = 6.4x106m.

16.Density of earth 5.522x103kg/m3.

17.Average angular velocity of the earth = 7.29x 10-5rad./sec

18.Average distance between the sun and earth = 1.5x1011m.

19.Average distance between moon and the earth =3.84x 108m.

20.Magnetic Moment of the earth = 6.4x 1021 Amp. X m2