 # Electrical Engineering Objective Questions { Electrostatics }

36. A parallel plate capacitor has capacitance of 10 af. If the linear dimensions of the plates area doubled andthe separation between them is also doubled the value of the capacitor would be

37. A parallel plate air capacitor has plates of 1,500 cm2 separated by 5 mm. If a layer of dielectric 2 mm thick and relative permittivity 3 is now introduced between the plates, then the new separation in mm between the plates, so that the capacitance value is unchanged, will be

38. A parallel plate capacitor with air dielectric is connected to a constant voltage source. The force between its plates is F. If the capacitor is immersed in a liquid of dielectric constant c without disconnecting it form the power supply, then the force between the plates would be

39. A parallel plate capacitor with air dielectric is charged and then disconnected from the supply. The force between the plates is F. If the capacitor is now immersed in a liquid of dielectric constant E, then the force between the plates will be e 2F

40. In a cable capacitor, voltage gradient is maximum at the surface of the

41. The time constant of an RC series circuit connected to a dc source is equal to t=0 I1V 2 RC

42. While testing a capacitor with ohmmeter, if the capacitor shows charging but the final resistance reading is appreciable less than normal the capacitor is

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