Experiment No . 3 ( B.Sc. 5th Semester Physics Project file )

Experiment No. 3 bsc.5th semester

To determine the refractive index of the material of a prism using sodium light.

Object

            To determine the refractive index of the material of a prism using sodium light.

Apparatus

            Spectrometer , sodium lamp (as monochromatic source prism or light glass) , reading lens , sprit level etc.

Formula

            The refractive index of the material of the prism is given by the formula.

                        μ = sin ( A + ₰m/2)/sin(A/2)

where A = Angle of the prism ₰m = Angle of minimum deviation.

Calculation

                                    μ = sin (A ₰m/2)/ sinA/2

                                    sin (60  ͦ + 37  ͦ/2) sin(60/2)

                                    sin (48.8)/sin30  ͦ

                                    μ = 1.49 answer

Observation table 

S . No .	Angle of incidence (Li)	Angle of deviation (LD)
1.	30  ͦ	40  ͦ
2.	40  ͦ	30.5  ͦ
3.	45  ͦ	31  ͦ
4.	55  ͦ	38  ͦ
5.	60  ͦ	40  ͦ

 

            L of prism = 60  ͦ

            A = L of prism

Result

            The angle of deviation D , first 37  ͦrefractive index of glass for sodium light μ = 1.49

Source of error and precautions

1.      A narrow slit must be used.

2.      All adjustments must be made carefully.

3.      For all readings make the left of the image of the slit coincide with the vertical cross = wire of the telescope.

 

•  Note

• (Please note: if a particular experiment is not visible, please search for it using the search box—for example, Experiment No. 4 To determine the refractive index of the material of a prism using spectrometer.

  कृपया ध्यान दीजिये अगला  एक्सपेरिमेंट न दिख रहा हो वो आप सर्च बॉक्स में सर्च कर लीजिये . जैसे , एक्साप्रिमेंट नंबर. 4 या फिर To determine the refractive index of the material of a prism using spectrometer.

Experiment No . 2 ( B.Sc. 5th Semester Physics Project file )

 Experiment No. 2 bsc.5th semester

To determine the wave length  of Laser beam using plane diffraction grating.

Object

            To determine the wavelength of laser beam using plane diffraction grating .

Apparatus

            Diode laser with power supply (λ = 670 nm) visible red region spectrometer circular table but without collimator and telescope , instead two holders are provided , one for holding the laser source and other for laser detector diffraction grating (usual 1500 λπ) nanometer to measure the cutout current spirit level e t c .

Formula

            (a + b) sin θ = nλ

Wavelength λ = ( a + b) sin θ/n
Λ = wavelength of laser
( a + b) = grating element
. n = order of spectra (n = 1 , e t c)
θ = angle of diffraction for order n.

Observation Table

            N = 1500 L .P . I

V₁	V₂	V₁ + V₂/2=d	D	θ
4.75	4	4.37	12.5	19.2696
4.5	3.25	3.77	10	20.65

 

Calculation

                                    . nλ = sin l /N

                                    . n = 1

                                    .λ = sin 19.2696x2.54/1500 cm

                                    λ₁ = 5585 Aͦ

                        λ₂ = sin 20.65 x 2.54/1500

                                    λ₂ = 5971 Aͦ

                                    λ = λ₁ + λ₂/2

                                    5585 + 5971/2

                                    11556/2

                                    Λ = 5778 Aͦ ans

Result

            To value of wavelength of the laser beam is found to be 57.78 Aͦ

Sources of Error and precaution

• Laser beam should not be locked at directly. It is hazardous to the eyes.
• 2.      Even looking at the secular reflections from smooth surface should be avoided.
• 3.      The laser is to be switched off after nothing observations or when not required.
• 4.      The laser and is power supply should never be tampered with when it is in ‘ON’ condition , the current is of the order of 10 mA at 2 kv.
• 5.      Laser experiments are to be performed only in the presence of the teacher.

         Note

• (Please note: if a particular experiment is not visible, please search for it using the search box—for example, Experiment No. 3 To determine the refractive index of the material of a prism using sodium light.

  कृपया ध्यान दीजिये अगला  एक्सपेरिमेंट न दिख रहा हो वो आप सर्च बॉक्स में सर्च कर लीजिये . जैसे , एक्साप्रिमेंट नंबर. 3 या फिर To determine the refractive index of the material of a prism using sodium light.

Physics (B.Sc 1st semester )

                                                                   Index

S.r.No.	Name of the Experiment	Page No.	Date of Experiment
1.	To determine the moment of inertia of flywheel about its own axis of rotation.	1..	..2026
2.	To determine the moment inertia of an inregular r’gid body about an axis passing through its center of gravity of perpendicular to its plane by dynamical method (Inertia table )	2	..2026
3.	To study the variation of T with L for a bar pendulum ( Compaund Pendulum ) To determine – Value of acceleration due to gravity ,the position of centre of gravity of a bar and radius of gyration K.	3	..2026
4.	To determine the modulus of rigidity of a wire by marwell’s Nedle.	4	…2026
5.	To determine the height of wire by Sertant	5	..2026
6.	To determine the Poisson’s ratio of Rubber Tube by using rubber Tube	6	..2026

         

      Note.

(Please note: if a particular experiment is not visible, please search for it using the search box—for example, Experiment No. 3.)

कृपया ध्यान दीजिये जो एक्सपेरिमेंट न दिख रहा हो वो आप सर्च बॉक्स में सर्च कर लीजिये . जैसे , एक्साप्रिमेंट नंबर.3