A. Cast-iron
B. Graphite
C. Rubber
D. Glass
Related Mcqs:
- The co-ordination number of a simple cubic structure is______________?
A. 2
B. 4
C. 6
D. 8 - Superconductors are becoming popular for use in________________?
A. generating very strong magnetic field
B. manufacture of bubble memories
C. generating electrostatic field
D. generating regions free from magnetic field - Mercury as an electric contact material is_______________?
A. a liquid
B. a metal
C. a metal liquid
D. a gas - Solder is an alloy of______________?
A. copper and aluminium
B. tin and lead
C. nickel, copper and zinc
D. silver, copper and lead - Most of the common metals have _________ structure?
A. linear
B. hexagonal
C. orthorhombic
D. cubic - The resistivity of a metal is a function of temperature because_____________?
A. the amplitude of vibration of the atoms varies with temperature
B. the electron density varies with temperature
C. the electron gas density varies with temperature - 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) - Which of the following materials is the best conductor of electricity ?
A. Tungsten
B. Aluminium
C. Copper
D. Carbon - Copper, even though costly, finds use in the windings of electrical machines because_____________?
A. copper points offer low contact resistance
B. copper can be easily soldered and welded
E. copper windings are less bulky and the machines become compact
D. all of the above - For a particular material the Hall coefficient was found to be zero. The material is______________?
A. insulator
B. metal
C. intrinsic semiconductor
D. none of the above
