Carbon electrodes are not used in_______________?

Related Mcqs:

1. A carbon resistor contains_____________?

   A. carbon crystals
   B. solid carbon granules
   C. pulverized coal
   D. finely divided carbon black

2. Carbon rods are used in wet and dry cells because_____________?

   A. carbon rod serves as conductor
   B. carbon can resist the attack of battery acid
   C. both (A) and (B)
   D. either (A) or (B)

3. Carbon resistors are used extensively because they are____________?

   A. easy to make
   B. compact
   C. inexpensive
   D. all of the above reasons

4. Carbon bearings are used under which of the following conditions ?

   A. Where lubrication is difficult or im-possible
   B. Where corrosive chemical action exists
   C. Where high temperature exists
   D. All of the above

5. The carbon percentage is least in__________________?

   A. low carbon steel
   B. wrought iron
   C. cast iron
   D. malleable iron

6. The tiny block formed by the arrangement of a small group of atoms is called the____________?

   A. unit cell
   B. space lattice
   C. either A. or (b)
   D. none of the above

7. The superconductivity is due to____________?

   A. the crystal structure having no atomic vibration at 0°K
   B. all electrons interact in the super-conducting state
   C. the electrons jump into nucleus at 0°K
   D. none of the above

8. Which of the following is the poorest conductor of electricity ?

   A. Carbon
   B. Steel
   C. Silver
   D. Aluminium

9. Addition of 0.3 to 4.5% silicon to iron ________ the electrical resistivity of iron?

   A. increases
   B. decreases
   C. does not change

10. For germanium the forbidden energy gap is_______________?

    A. 0.15 eV
    B. 0.25 eV
    C. 0.5eV
    D. 0.7eV