A. Diamond
B. High speed steel
C. Mild steel
D. Cast iron
Related Mcqs:
- 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 - ___________ is most commonly used for making magnetic recording tape?
A. Silver nitrate
B. Ferric oxide
C. Small particles of iron
D. Silicon-iron - Commonly used conducting materials are_____________?
A. copper
B. aluminium
C. both (A) and (B)
D. copper and silver
E. platinum and gold - highest conductivity_____________?
B. lowest temperature co-efficient
C. good mechanical strength
D. good corrosion resistance
E. easy solderable and drawable quality
F. all of the above - An H.R.C. fuse is_______________?
A. a ceramic body having metal and caps
B. a wire of platinum
C. a heavy cross-section of copper or aluminium
D. a ceramic tube having carbon rod inside it - In thermocouples which of the following pairs is commonly used ?
A. Copper-constantan
B. Aluminium-tin
C. Silver-German silver
D. Iron-steel - Non-linear resistors______________?
A. produce harmonic distortion
B. follows Ohm’s law at low temperatures only
C. result in non-uniform heating
D. none of the above - The conductivity of a metal is determined by____________?
A. the electronic concentration and the mobility of the free electrons
B. the number of valence electrons per atom
C. either (A) or (B)
D. none of the above - Which of the following high resistance materials has the highest operating temperature ?
A. Kanthal
B. Manganin
C. Nichrome
D. Eureka - The photo-electric effect occurs only when the incident light has more than a certain critical____________?
A. intensity
B. speed
C. frequency
D. wave length
