Engineering Physics Practicals - Data of physical Constants

                             Data of physical Constants

1. Young’s modulus of wood = 1×10¹⁰  Nm^-2

2. Rigidity modulus of the material of the wire

Material of the wire	1010  Nm-2
Brass	3.4 – 3.5
Iron (cast)	3.5 – 5.3
Iron (Wrought)	7.7 – 8.3
Steel (Cast)	7.4 – 8.3
Steel (Mild)	8.9
Copper	3.4 – 3.6

3. Viscosity of water = 0.81 × 10^-3 Nsm^-2

    Viscosity of kerosene = 0.0020 Nsm^-2

4. Wavelength of the lines of prominent mercury source

Colour	Nm
Voilet – I	404.4
Voilet – II	407.8
Blue	435.8
Greenish blue	491.6
Green	546.1
Yellow – I	576.1
Yellow – II	579.1
Red	620.4

5. Particle size of lycopodium powder = 3.4×10^-5 m

6. Thermal conductivity

Substance	W m-1 K-1
Cardboard	0.04
Glass	1.00
Ebonite	0.7

7. Compressability of different liquids

S.No	Liquid	m2 N-1
1.	Benzene	9.1 ×10-10
2.	Kerosene	7.5×10-10
3.	Castor Oil	4.7×10-10
4.	Water	4.59×10-10

8. Thickness of a thin wire = 5×10^-5 m

9. Dispersive power of the material of the prism.

                             Crown – 0.015

                   Dense crown – 0.018

10. Wavelength of laser source                   = 690 nm

11. Band Gap

Semiconductor	ev
Germanium	0.67
Silicon	1.12