A beam of 4-0 keV electrons from a source is incident on a target 50.0 cm away. Find the radius of the electron beamspot due to Heisenberg's uncertainty principle.

Calculate the lowest energy of an electron confined to move in a 1-dimensional potential well of width 10 mm

Estimate the de Broglie wavelength of the electron orbitting in the first excited state of the hydrogen atom.

Show that the lines in the absorption spectra corresponding to the rotational transitions from two adjacent energy levels of a medium sized molecule at room temperature have comparable intensities.

Given the force constant of HCl molecule 516 determine the wave number of the fundamental mode of vibration of the molecule. How many transition lines one can expect in the vibration spectra of HCl molecule at room temperature?

Evaluate the most probable distance of the electron from nucleus of a hydrogen atom in its 2p state. What is the probability of finding the electron at this distance?

Using Schrodinger equation, obtain the eigenfunctions and eigenvalues of energy for a I-dimensional harmonic oscillator. Sketch the profiles of eigenfunctions for first three energy states.

Calculate the probability of transmission of an electron of 1·0 eV energy through a potential barrier of 4·0 eV and 0·1 nm width,

Explain Stokes and anti-Stokes Raman scattering with the help of energy level diagram. For a diatomic molecule, obtain expressions for transition energies of its Raman spectra with rotational fine structure and hence the 'wave numbers of the Stokes Lines.

Explain why lines in some Raman spectra are found to be plane polarized to different extents even though the exciting radiation is completely unpolarized

State Franck-Condon principle. Define Franck-Condon factors. Using schematic diagram, explain the decay of excited states leading to the phenomena of fluorescence and phosphorescence.

Explain why the square the angular momentum and only one of the components Ly, Lz) of L are regarded as constants of motion.

Explain the principle of Nuclear Magnetic Resonance with the help of an energy level diagram. Give examples of nuclei which exhibit NMR. What major inferences can be drawn from an NMR spectra

In an NMR experiment, hydrogen atoms are subjected to a magnetic field of 5.0 T. Determine the difference in energy between two spin states of the nuclei of hydrogen atom and the frequency of radiation required for NMR.

Estimate the order of nuclear radius of lead 82) using the large angle (back) scattering of alpha particles of energy 10 MeV incident on a target (lead). [Given: 9x 10^9 Nm^2

Distinguish between charge independence and charge symmetry of nuclear force. Give one example for each of these.

Describe briefly how parity violation in l3-decay was experimentally observed? What do you understand by the statement, 'neutrinos are left-handed'

The energy and wave vector for a conduction band electron ill a semiconductor are related as E a h^2k^2/mo where a is a constant and 1110 is the free electron mass. Calculate the effective mass of the electron.



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Consider the operational amplifier circuit given above: Given, R1 10 k.ohm. R2 150 k.ohm and the product of the open loop gain of the amplifier and its bandwidth 10^6 Hz. Determine the closed loop bandwidth of the amplifier.

Write two properties of deutron which support the existence of non-central tensor force.

Given that the deutron magnetic moment operator (in units of nuclear magneton) can be expressed as

Md MnOn MpOp 1/2l

where l is the relative angular momentum between neutron and proton and up are the Pauli spin operators and Mn and Mp are the respective magnetic moments. Find out the D-state probability of deutron wave function. [Given: Md 0.857 Mn, Mn -1·913 MN and Mp 2·793 MN; MN (nuclear magneton)]

How does one explain the approximate constancy of average binding energy per nucleon of nuclei in the region 30 A 170 in the plot of BE/A versus mass number

Write the semi-empirical mass formula pointing out the role of volume term, surface energy tem1, coulomb and symmetry energy correction terms.

State the three characteristic properties of strong, weak and electromagnetic forces distinguishing one from the other.

Point out the interactions in which the following conservation laws are obeyed or violated

Isotopic spin

Hyper charge

Lepton number

Charge conjugation

Write down the quark constituents of each of the following:







LO

n­

A system of paramagnetic atoms per unit volume) which can occupy only two energy levels in a uniform external magnetic field H is at a temperature T. If this system follows Boltzman's distribution, find the magnetisation and susceptibility of the system.

Obtain the expression for penetration depth using London's equation of superconductivity and explain its significance.

In a semiconductor, the effective masses of an electron and a hole are 0·07 mo and 0-4 respectively, where mo is the free electron mass. Assuming that the average relaxation time for the hole is half of that for the electrons, calculate the mobility of the holes when the mobility of the electrons is 0·8 m^2 volt^-1



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An amplifier in common-emitter configuration is shown in the above figure.
If the current gain B 100 and the a.c. emitter resistance 25·0 ohm, determine the input impedance and the voltage gain of the amplifier.


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Given above is a circuit of self biased p-channel JFET.
If the pinch off voltage is 5·0 V and VDs 6·0 calculate the saturation current IDss.

8.(c)Draw a schematic diagram of the single particle energy levels in a shell model including the effect of spin-orbit coupling. Show how it explains magic numbers in nuclei. Give two examples to show how this scheme predicts the spins and particles of odd A nuclei.