Past Questions
What are the differences between a JFET and a BJT? Draw and explain the static characteristics of an n-channel JFET. What is pinch-off voltage?
Explain how Newton’s rings are formed. Show that the wavelength of monochromatic light can be determined from Newton’s ring experiment.
State Ampere circuital law and explain how it was modified to include the displacement current.
What are Coriolis forces? Show that the total Coriolis force acting on a body of mass in a rotating frame is -2mω×v, where ω is the angular velocity of rotating frame and v is the velocity of the body in rotating frame.
What is the effect of periodic potential on the energy of electrons in metal? Explain it on the basis of Kronig-Penny model and explain the formation of energy bands.
What are de Broglie waves? Show that the de Broglie wavelength of a particle of momentum p is h/p (where h is Planck’s constant). The uncertainty in the location of a particle moving with a velocity of 7.28×10^7m/s is double of its de Broglie wavelength. Find out the uncertainty in measuring the velocity.
Determine the ground state parity, the magnetic moment and Quadrupole moment for the following nuclei Si29, Cl35 and Co60.
Define the term Q factor and sharpness of resonance for a resonant circuit. What will happen to series resonant circuit if resistance of the circuit is doubled? What will be the effect on resonant frequency?
Explain the fine structure of hydrogen line of the hydrogen spectra on the basis of the vector atom model.
Make a précis of the following: The assault on the purity of the environment is the price that we pay for many of the benefits of modern technology. For the advantages of automotive transportation we pay a price in smog-induced diseases, for the powerful effects of new insecticides, we pay a price in dwindling wildlife and disturbances in the relation of living things and their surroundings; for nuclear power, we risk the biological hazards of radiation. By increasing agricultural production with fertilizers, we increase water pollution. The highly developed nations of the world are not only the immediate beneficiaries of the good that technology can do; they are also the first victims of the environmental diseases that technology breeds. In the past, the environmental effects which accompanied technological progress were restricted to a small place and a relatively short time. The new hazards are neither local nor brief. Modern air pollution covers vast areas of continents. Radioactive fallout from nuclear explosions is worldwide. Radioactive pollutants now on the Earth’s surface will be found there for generations and in the case of carbon 14 for thousands of years.
You are a resident of Tuikhuahtlang, Aizawl. Write a letter to the Editor, Aizawl Times in about 150-200 words on the misuse and poor maintenance of the public park in your city. You may suggest measures for improvement and renovation.
Write an essay on any one of the following topics in about 500 words: - Ban on plastic: Environment vs. Economy - Organic Farming in India - Impact of climate change on global economic stability and development.
Explain the principle of operation of Permanent Magnet Moving Coil (PMMC) instrument with proper circuit diagram and also derive the torque equation developed by PMMC.
Define ferromagnetism and ferromagnetic material. How the hysteresis loop affects the operation of electrical machines?
Define Frequency modulation (FM) broadcasting. Describe FM transmitter through block diagram based on indirect and direct methods.
With a neat schematic diagram explain the working of a nuclear power plant.
A control system is described as below: dx/dt = Ax + Bu and y = Cx where, A = [matrix], x(0) = [vector], B = [vector] and C = [vector]. Determine the time response.
Draw the block diagram of 8085 microprocessor and explain in detail.
Explain the principle of operation of 3 phase Induction Machine.
Calculate current in each branch of the circuit shown in Figure.
A transformer is rated at 100 kVA. At full load its copper loss is 1.1 kW and its iron loss is 0.9 kW. Calculate (i) the efficiency at full load, unity power factor, (ii) the efficiency at half load, 0.9 power factor, and (iii) the load kVA at which maximum efficiency will occur.
Describe a 3-phase 120 degree mode voltage source inverter operation with the help of voltage waveforms, switching pulses and respective circuit diagrams.
Describe breakdown of gas, liquid, and solid dielectric.
A light alloy having tensile strength is:
The part of the human brain concerned with sight is the: