Recently Active Optics Questions

1)The barrier potential of a sillicon p-n junction is 0.7 V. Can we measure it using voltmeter. 2)Which one will you prefer for the rectification of low AC voltages - a Si diode or a Ge diode? Why? 3)Why a transistor cannot b ...

as eureka stated lets put up some problemss that might be of good help for jee 2009 revision aspect. i just did not want to mix it up with his thread and make it go unnoticed like my chemistry hub 1}show that the focal length ...

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How can v increase the work-function of Tungsten??? ...

STATEMENT-1: When a Coolidge tube is operated for some time it becomes hot. STATEMENT-2: The electrons emitted by the filament of the Coolidge tube hit the target with a very high speed which then stopped by the target. (a) S ...

calculate the radii of frensel zones of a plane wave for a point b removed from the wave front by a distance of b>>λ, where λ is the wavelength of the source. ...

FRee neutrons decay into protons but free protons never decay Neutrons are slightly heavier than protons are both the statements true If yes please explain ...

In a photoelectric effect setup , a point source of light of power 3.2*10^-2 W emits mono energetic photons of energy 5.0ev.The source is located at a distance of .8m from the center of a stationary metallic sphere of work fu ...

a beam of light incident vertically on a glass hemisphere of radius R and refractive index √2 lying with its plane side on a table. the axis of beam concides with the verticle axis passing through the centre of base of the ...

*Image* the graph between distance u and image distance v for a lens is given below . the focal length of lens is (a) 5 ± 0.1 (b) 5 ± 0.05 ...

In an experiment performed with electrons of energy 4eV, the wavelength of the electrons was measured by diffracting them from a crystal. The momentum of the electrons is now doubled. The wavelength of the electrons, after th ...

*Image* a glass prism with respective index 1.5 is immersed in water (refractive index 4/3 ). a light beam incident normally on the face AB is totally reflected to reach the face BC if (a) sin θ >8/9 (b)2/3 < sin θ &l ...

A point source of light is placed at a distance h below the surface of a large and deep lake.Show that the fraction for the light energy that escapes directly from water surface is independent of height h and it is given by f ...

Q1) A 35 mm slide with a 24 mm*36 mm picture is projected on a screen placed 12 m from the slide.The image of the slide picture on the screen measures 1.0 m *1.5 m.Determine the location of the projection lens, and its focal ...

can the formation of the virtual and real image can be explained by wave theory if so pls explain ...

A rod of glass μ=3/2 and of square of cross section is bent into the shape shown in *Image* A parallel beam of light falls perpendicularly on the plane flat surface A.Referring to the diagram,d is the width of the side and R ...

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two radioactive substances X and Y emit alfa and beta particles respectively Their disintegration constants are in the ratio 2:3 To have equal probabilities of getting emission of alfa and beta particles the ratio of number o ...

at what distance from each other should 2 men stand for an eye to distinguish them from a distance of about 11 km. the resolving power of a normal eye is approximately 1. ...

why does the moon ,purely white in the daytime have a yellowish hue after sunset? ...

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Q1 If μo and εo represent permeablity and permittivity of vacuum and μ and ε be the permittivity and permeablity of medium,then calculate refractive index of medium. Q2 In an npn transistor circuit,the collector current i ...

What will happen to angle of min deviation in case of prism if we change frequency of light.. ...

Some Scientists have predicted that a global winter war on earth would occur be followed by 'nuclear winter'.What would cause nuclear winter? PLZZ HELP ME OUT!!!!!!![4][4][4][4][4][4] ...

Q. Consider an excited hydrogen atom in state n moving with a velocity v(v<<c). It emits a photon in the direction of its motion and changes its state to a lower state m. Apply momentum and energy conservation principle ...

a ray of light is incident at an angle a on the boundary separating two transparent media It is transmitted If the angle of incidence is very slightly increased the ray gets reflected in the same medium The difference between ...

A THIN COAT OF TRANSPARENT SUBSTANCE WITH A REFRACTION INDEX `n` LOWER THAB THAT OF THE GLASS IS APPLIED TO THE SURFACE OF OPTICAL GLASS[COATED GLASS] TO REDUCE ITS REFLECTION FACTOR[REFLECTANCE].ESTIMATE THE THICKNESS OF THE ...

A PLANE -CONVEX LENS WITH A RADIUS OF CURVATURE R2<R1 IS PLACED WITH ITS CONVEX SIDE ON TO THE SURFACE OF A PLANE CONCAVE LENS HAVING A RADIUS OF CURVATURE R1. FIND THE RADII OF NEWTON`S RINGS THAT APPEAR AROUND THE POINT ...

the word MANISH is written on a sheet of white paper with a red pencil and the word NISHANT with a green pencil. a green and red pieces of glasses are available. through which glass can the word MANISH be seen? ...

CLACULATE THE RADII OF THE FRENSEL ZONES OF A SPHERICAL WAVE WITH A RADIUS a FOR POINT B REMOVED BY A DISTANCE OF a+b FROM A SOURCE OF MONOCROMATIC WAVES WITH A LENGTH OF λ,BEARING IN MIND THAT a>>λ ,, b>>λ. ...