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General Knowledge :: Physics

  1. A potentiometer wire is 100 cm long and a constant potential difference is maintained across it. Two cells are connected in series first to support one another and then in opposite direction. The balance points are obtained at 50 cm and 10 cm from the positive end of the wire in the two cases. The ratio of the emf's is :

  2. A.

     3:4

    B.

     5:4

    C.

     5:1

    D.

     3:2


  3. Suppose voltage V is applied across a resistance R. The power dissipated in the resistance is P. Now the same voltage V is applied across a parallel combination of three equal resistors each of resistance R. Then the power dissipated in the second case will be

  4. A.

     P

    B.

     3P

    C.

     P/3

    D.

     2p/ 3


  5. A galvanometer can be converted into a voltmeter by connecting with it a

  6. A.

     High resistance in parallel

    B.

     Low resistance on parallel

    C.

     High resistance on series

    D.

     Low resistance in series


  7. In superconductors, the energy gap is due to

  8. A.

     Electron-electron interaction

    B.

     Electron-phonon interaction

    C.

     Phonon-phonon interaction

    D.

     Electron-photon intercation


  9. Electrical Pressure is also called

  10. A.

     Current

    B.

     Voltage

    C.

     Resistance

    D.

     Power


  11. The ''Choke' used with a tube light is basically

  12. A.

     An inductor

    B.

     A capacitor

    C.

     A transformer

    D.

     A resistor


  13. For photoelectric effect to take place, the metal used as the cathode should have ________

  14. A.

     High melting point

    B.

     Low melting point

    C.

     Low work function

    D.

     Low resistance


  15. Which phenomena shows the particle nature of light?

  16. A.

     Diffraction

    B.

     Interference

    C.

     Photoelectric effect

    D.

     Polarisation


  17. According to the quantum theory of light, the energy of light is carried in discrete units are called

  18. A.

     Photoelectrons

    B.

     Protons

    C.

     Electrons

    D.

     Photons


  19. Photon is the fundamental unit/quantum of

  20. A.

     Gravitation

    B.

     Electricity

    C.

     Magnetism

    D.

     Light