Possible One mark Questions

 

1. The value and the unit of permittivity are ……… and ……… respectively.

2. The electric field at any point outside the two oppositely charged parallel plates is ………….

3. The principle of the lightning conductor is ………………

4. Smaller the radius of curvature of a conductor, ……………. is the surface charge density.

5. The energy stored in a capacitor is U = …………..

6. The induced dipole moment is directly proportional to the ………… field.

7. If the centre of gravities of the positive and the negative charges coincide, it is ….…… molecule.

8. The process of isolating a certain region of space from external electric field is called ………….

9. The potential at a point at a distance 3m from a point charge 9 μC is ………….

10. In an uniform electric field, equipotential surfaces are the ……….. planes.

11. The number of electric lines of force originating from a charge of 1 C is …………..

12. The electric field at any point inside a hollow charged metallic sphere is ………..

13. The capacitance of a parallel plate capacitor increases from 6 μF to 60 μF when a dielectric is filled between the plates. The dielectric constant value is ……………

14. The electric field at any point inside the two oppositely charged parallel plates is ………….

15. The unit of electric field intensity is ………….

16. Fuse wire contains ………… % of lead and ………….. % tin.

17. At the temperature of inversion, the thermo emf is …………..

18. The torque is maximum on a current carrying coil, if the plane of the coil is …………. to the field.

19. An ideal voltmeter has ……………. resistance.

20. Magnetic moment of a current carrying loop is the product of ……….. and …………….

21. All the elements are made up of atoms of hydrogen. This was suggested by ……………..

22. In the case of hydrogen atom, Thomson’s model gives only one spectral line of wavelength about …….

23. The radius of the n th orbit of an electron is proportional to the square of the ………… number.

24. The wavelengths of the D1 and D2 emission lines of sodium are ……… and ………..

25. When an electric field or magnetic field is applied to the atom, each of the spectral line is split into several lines. The former is called as ……… effect and the later is called as ………. effect.

26. Any plane containing an arrangement of atoms symmetrically in a three dimensional space is called …...

27. In characteristic X – rays, when an electron jumps from M shell to N shell, ………. line is formed.

28. In metastable states, the life time of the atoms is ………… second.

29. According to Bohr’s atom model, ………… quantity takes discrete values.

30. In a ruby laser, ………….. ions absorb the green color.

31. The maximum kinetic energy of the photo electrons is ………….. proportional to the frequency of the incident radiation.

32. Light is emitted in the form of discrete packets of energy called …………….

33. In order to get large number of photo electrons, the plate is coated with a low work function material like ……..

34. Photoelectric cells are used in the study of ……….. and …………. of stars.

35. The equation of de Broglie waves is λ = 12.27 A0 / ( ……)1/2

36. The resolving power of an electron microscope depends on the ……… of the radiation.

37. The types of the photo electric cells are ……… , ………. , ……….

38. The special theory of relativity was formulated by ……………….

39. The stationary orbits of the electrons are those in which orbital circumference is an integral multiple of de Broglie …………..

40. The relation between the rest mass and the mass of the particle when it moves with a velocity v is …………..

41. The mass of the proton is ……….. times the mass of the electron.

42. 13 Al 27 and 14 Si 28 are the examples for …………

43. The nuclear force is …………. times the gravitational force.

44. The nuclear fission can be explained by ……………model.

45. The isotope used in agriculture is …………

46. The half life period of an isolated neutron is ………… minutes.

47. The HLP of N 13 is 10.1 minutes. The mean life period is …………

48. The betatron can accelerate particles to energy in the order of …………….

49. The sun radiates the solar energy at the rate of ………… joules per second.

50. The mass of the ………. vary from 2180 me and 3275 me.

51. For an insulator, the forbidden energy gap is in the order of ……………..

52. In a PN junction diode reverse bias, the current is of the order of ………….

53. The conversion of AC into DC is called ……………….

54. The ratio of the d.c power output to the a.c power input is known as rectifier ……………

55. In a Zener diode, at a particular reverse bias voltage called …………… , the current increases enormously.

56. In a transistor, the ratio between emitter-base potential and base current is called ………….

57. The frequency interval between lower cut off and upper cut off frequencies is called ……………

58. In Colpitt’s oscillator, the frequency of oscillation is given by f = ………….

59. First De Morgan’s theorem is ………………….

60. OP-AMP consists of …….. transistors, ……. resistors and ……… capacitor.

61. In amplitude modulation, the bandwidth is ………… times the signal frequency.

62. The purpose of dividing each frame into two fields so as to transmit 50 views of the picture per second is to ………… in the picture.

63. Printed documents to be transmitted by fax are converted into electrical signals by the process of …………

64. The long distance radio communication is possible through …………… wave propagation.

65. The factor that determines the strength and quality of the transmitted signal is called ……………..

66. A carrier wave of amplitude 10 mV is modulated by a sinusoidal audio signal of amplitude 6 mV, the modulation factor is ……………..

67. If 900 kHz station is tuned, then the frequency of the waves produced by the local oscillator is ……… kHz.

68. The number of synchronizing pulses that are used for transmission is equal to …………..

69. In a 625 line system, the horizontal frequency of scanning is equal to …………… Hz.

70. In a CCIR standards the channel width for the TV transmission is ……………….. Hz.