Discuss lasing action of a He-Ne laser.
See Answer →A current is flowing in an infinitely long straight wire. Using Biot-Savart law, show that the resultant magnetic field at a point along a line perpendicular to the wire is inversely proportional to the distance of the point from the wire.
See Answer →Define numerical aperture and angle of acceptance. An optical fiber has a numerical aperture of 0.20 and cladding refractive index of 1.59. Calculate the refractive index of the core material and the acceptance angle of the fibre in water whose refractive index is 1.33.
See Answer →A vertical single and double slits and illuminated by a point source. Discuss the salient features of their Fraunhofer diffraction patterns. Also, obtain an expression for intensity distribution in case of double slit.
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The inclined faces of a glass biprism (µ = 1.5) make an angle of 1° with its base. The biprism is illuminated by a sodium lamp (2. = 589 nm) and the eye piece is at a distance of 1 m from the slit. A convex lens inserted between the biprism and the eye piece gives clear images of coherent sources in the focal plane of the eye piece. If the images are 0.4 cm apart in one case and 0.16 cm apart in the second case, calculate the width of interference fringes observed on the screen.
See Answer →Show that the radius of a dark Newton's ring is directly proportional to the square root of the radius of curvature of the lens used.
See Answer →Discuss the principle of Michelson interferometer. How can it be used to determine the refractive index of a thin plate and wavelength of monochromatic light?
See Answer →A uniform plane wave of 100 kHz travelling in free space strikes a large block of a material having and Q = 0 normal to the surface. If the incident electric field vector is given by
E = 100 sin () xˆ V
write the complete expressions for the incident, reflected, and transmitted field vectors.
See Answer →Obtain an expression to show that the change in the quantity of charge enclosed in an arbitrary volume is accompanied by a net flow of charge inwards or outward across the surface of the enclosed volume.
See Answer →How is image formed on the retina of human eye processed by human brain? Discuss.
See Answer →Show that superposition of two linearly polarised light waves having different amplitudes and a finite phase difference can be used to produce elliptically plane polarised waves.
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The energy of a capacitor is 4.0 J after it has been charged by a 1.5 V battery. Calculate its energy when it is charged by a 6.0 V battery.
See Answer →A plane e.m. wave is incident normally on an interface. Obtain expressions for reflection and transmission coefficients.
See Answer →Determine the value of equivalent capacitance between points A and B for the combination of capacitors shown in the Figure below:
Discuss the importance of hologram in (i) information storage, and (ii) pattern recognition.
See Answer →Explain the phenomenon of polarisation of a dielectric. Show that, when a dielectric material is filled between the plates of a capacitor, the value of capacitance increases by factor of K, the dielectric constant of the material.
See Answer →'Diffraction limits the image forming capability of optical devices'. Discuss the authenticity of this statement for the particular case of a microscope.
See Answer →Discuss, with necessary theory, how is interference pattern in Young's double slit experiment modified when a thin glass plate is introduced in the path of one of the interference waves?
See Answer →Discuss the significance of accommodation and convergence of human eye in respect of perception of light.
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