Random collection of Physics Viva Questions

  1. State the Principle of a potentiometer. (The students say that potential drop is proportional to length but the constant quantities are not mentioned)
  2. How can we increase the sensitivity of a potentiometer?
  3. Define figure of merit of a galvanometer.
  4. Which has more resistance – a galvanometer or a milliammeter?
  5. How does an LED emit light?
  6. What is the difference between an ordinary diode and an LED?
  7. Define principal axis of a convex lens?
  8. What happens to the focal length of a concave mirror if it is immersed in water?
  9. What are the factors affecting the internal resistance of a cell?
  10. What are the difference between primary and secondary cell?
  11. Why can’t we use a dry cell for starting a car?
  12. What happens to the resistivity of a wire when it is doublefolded?
  13. How does the resistance of a wire depend on its dimensions?
  14. Why are the resistances used in a resistance box is like 1,2,2,5,10,20,20,50,100,200,200,500,1000,2000,2000,5000 etc?
  15. Why constantan or manganin wires are used for making the resistance coils in resistance box?
  16. What is a standard resistance?
  17. What are the characteristics of a standard resistance?
  18. What are the precautions to be observed while doing electricity experiments in general?
  19. What is a galvanometer?
  20. What is the resistance of an ideal ammeter?
  21. Why is ammeter always connected in series and voltmeter always connected in parallel?
  22. How can we convert a galvanometer into an ammeter or a voltmeter?
  23. What is shunt?
  24. What is AVO meter?
  25. What is the effect of temperature on the resistance of a conductor?
  26. Why does the resistance of a conductor increases with temperature, whereas that of a semiconductor decreases with temperature.
  27. What is conductance?
  28. What are non ohmic devices? give an example.
  29. What are superconductors?
  30. Define emf
  31. Why emf is said to be a misnomer?
  32. What happens if the battery used in the primary circuit of a potentiometer has less emf compared to the emf of the cell used in the secondary circuit?
  33. If you find that the galvanometer reading is shaky, what error can you expect?
  34. What do you mean by figure of merit of a galvanometer?
  35. Why a moving coil galvanometer is called so?
  36. What is the principle of a galvanometer?

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Interesting News in Physics

Dancing in the quantum world – physicsworld.com

A new project known as “Danceroom Spectroscopy” represents a genuine fusion of art and science, resulting in an impressive visual art show that is driven by real physical laws.

The project’s mastermind is David Glowacki, a researcher at the University of Bristol in the UK. In this special video report, Glowacki talks to Physics World journalist James Dacey about his stimulus for the project and how the technology involved was inspired by some of the concepts from his research in theoretical chemistry. Glowacki describes how the project came about through a conversation with a friend about making music via motion. “What we quickly found out was that the idea had been done to death, so I came up with a more interesting way of attacking that problem,” he explains.

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Find below a collection of interesting Articles I came across while Browsing the web. Links are provided to the original website for complete reference   LATEST PHYSICS NEWS http://feeds.feedburner.com/physicsnews Can The Invisible Man See?  ...

Rev. William R. Callahan Dies at 78, Dissident Who Challenged Vatican – New York Times

Rev. William R. Callahan Dies at 78, Dissident Who Challenged VaticanNew York TimesHe had hoped to be an agronomist, but the Jesuits asked him to study physics because they needed physics professors in their universities. ...

AERB experts lay to rest – Times of India

AERB experts lay to restTimes of IndiaRumours about radioactive material stored in the physics department doing the rounds well over a month now had led to a panic wave within the university and ...and more »

Karole Armitage's 'Three Theories' finds a muse in physics – Albany Times Union

Albany Times UnionKarole Armitage's 'Three Theories' finds a muse in physicsAlbany Times Union... quantum mechanics, these two pillars of 20th-century physics, and reveals the fact that these two highly tested theories are incompatible,&quo...