A. carbon crystals
B. solid carbon granules
C. pulverized coal
D. finely divided carbon black
Related Mcqs:
- Carbon electrodes are not used in_______________?
A. GLS lamps
B. electric arc furnace
C. dry cells
D. cinema projectors - 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) - Carbon resistors are used extensively because they are____________?
A. easy to make
B. compact
C. inexpensive
D. all of the above reasons - 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 - The carbon percentage is least in__________________?
A. low carbon steel
B. wrought iron
C. cast iron
D. malleable iron - Which of the following materials is preferred for transmitting electrical energy over long distance ?
A. Copper
B. Aluminium
C. Steel reinforced copper
D. Steel reinforced aluminium - The coils of D.C. motor starter are wound with wire of_______________?
A. copper
B. kanthal
C. manganin
D. nichrome - A good electric contact material should have all of the following properties except_____________?
A. high resistivity
B. high resistance to corrosion
C. good thermal conductivity
D. high melting point - The number of atoms per unit cell in B.C.C. structure is_____________?
A. 1
B. 2
C. 4
D. 8 - ___________ has the best damping properties?
A. Diamond
B. High speed steel
C. Mild steel
D. Cast iron
