Science (English Medium) इयत्ता १२ - CBSE Question Bank Solutions

The intensity at the central maxima in Young’s double slit experimental set-up is I₀. Show that the intensity at a point where the path difference is λ/3 is I₀/4.

A hollow metal sphere of radius 10 cm is charged such that the potential on its surface is 5 V. What is the potential at the centre of the sphere?

In Young’s double slit experiment to produce interference pattern, obtain the conditions for constructive and destructive interference. Hence deduce the expression for the fringe width.

How does the fringe width get affected, if the entire experimental apparatus of Young is immersed in water?

In what respect is a toroid different from a solenoid? 

 Draw and compare the pattern of the magnetic field lines in the two cases ?

How is the magnetic field inside a given solenoid made strong?

Calculate the speed of light in a medium whose critical angle is 30° ?

Plot a graph showing the variation of stopping potential with the frequency of incident radiation for two different photosensitive materials having work functions W₁ and W₂ (W₁ > W₂). On what factors does the (i) slope and (ii) intercept of the lines depend?

The energy levels of an atom are as shown below. Which of them will result in the transition of a photon of wavelength 275 nm?

Which transition corresponds to emission of radiation of maximum wavelength?

Draw a circuit diagram to study the input and output characteristics of an n-p-n transistor in its common emitter configuration. Draw the typical input and output characteristics.

Explain, with the help of a circuit diagram, the working of n-p-n transistor as a common emitter amplifier.

How is a zener diode fabricated so as to make it a special purpose diode? Draw I-V characteristics of zener diode and explain the significance of breakdown voltage.

Explain briefly, with the help of a circuit diagram, how a p-n junction diode works as a half wave rectifier.

Can we perform Young's double slit experiment with sound waves? To get a reasonable "fringe pattern", what should be the order of separation between the slits? How can the bright fringes and the dark fringes be detected in this case?

If the separation between the slits in a Young's double slit experiment is increased, what happens to the fringe-width? If the separation is increased too much, will the fringe pattern remain detectable?

Suppose white light falls on a double slit but one slit is covered by a violet filter (allowing λ = 400 nm). Describe the nature of the fringe pattern observed.

The slits in a Young's double slit experiment have equal width and the source is placed symmetrically with respect to the slits. The intensity at the central fringe is I₀. If one of the slits is closed, the intensity at this point will be ____________ .

A thin transparent sheet is placed in front of a Young's double slit. The fringe-width will _____________ .

If Young's double slit experiment is performed in water, _________________ .