Current Electricity

41. International ohm is defined in terms of the resistance of

1. a column of mercury
2. a cube of carbon
3. a cube of copper
4. the unit length of wire

View answer

42. It becomes more difficult to remove

1. any electron from the orbit
2. first electron from the orbit
3. second electron from the orbit
4. third electron from the orbit

View answer

43. Nichrome wire is an alloy of

1. lead and zinc
2. chromium and vanadium
3. nickel and chromium
4. copper and silver

View answer

44. Ohm's law is not applicable to

1. vacuum tubes
2. carbon resistors
3. high voltage circuits
4. circuits with low current densities

View answer

45. One newton meter is same as

1. one watt
2. one joule
3. five joules
4. one joule second

View answer

46. Out of the following which is an insulating material?

1. Copper
2. Gold
3. Silver
4. Paper

View answer

47. Out of the following which is not a poor conductor?

1. Cast iron
2. Copper
3. Carbon
4. Tungsten

View answer

48. Resistance of 220 V, 100 W lamp will be

1. 4.84 Q
2. 48.4 Q
3. 484 ft
4. 4840 Q

View answer

49. Resistance of a material always decreases if

1. temperature of material is decreased
2. temperature of material is increased
3. number of free electrons available become more
4. none of the above is correct

View answer

50. Resistance of a tungsten lamp as applied voltage increases

1. decreases
2. increases
3. remains same
4. none of the above

View answer