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
Related Mcqs:
- 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 variety of copper has the best conductivity ?
A. Induction hardened copper
B. Hard drawn copper
C. Pure annealed copper
D. Copper containing traces of silicon - Due to which of the following reasons copper and aluminium are not used for heating elements ?
A. Both have great tendency for oxidation
B. Both have low melting point
C. Very large length of wires will be required
D. All of the above - Due to which of the following fact, in India, aluminium is replacing copper ?
A. Aluminium is more ductile and malleable than copper
B. Aluminium is available in plenty, cheaper and lighter than copper
C. Aluminium has lower resistivity than that of copper
D. Aluminium has less temperature co-efficient than copper - 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 - Which of the following affect greatly the resistivity of electrical conductors ?
A. Composition
B. Pressure
C. Size
D. Temperature - Addition of 0.3 to 4.5% silicon to iron ________ the electrical resistivity of iron?
A. increases
B. decreases
C. does not change - A carbon resistor contains_____________?
A. carbon crystals
B. solid carbon granules
C. pulverized coal
D. finely divided carbon black - The forbidden gap in an insulator is________________?
A. large
B. small
C. nil
D. any of the above
