Question: Which of the following materials is used for making coils of standard resistances ?

• 1. Copper
• 2. Nichrome
• 3. Platinum
• 4. Manganin

Question: Copper, even though costly, finds use in the windings of electrical machines because_____________?

• 1. copper points offer low contact resistance
• 2. copper can be easily soldered and welded
• 3. copper windings are less bulky and the machines become compact
• 4. all of the above

Question: Which of the following is an advantage of stranded conductor over equivalent single conductor ?

• 1. Less liability to kink
• 2. Greater flexibility
• 3. Less liability to break
• 4. All of the above

Question: Substances whose specific resistance abruptly decreases at very low temperature are called___________?

• 1. insulators
• 2. conductors
• 3. semiconductors
• 4. superconductors

Question: is the property of absorbing moisture from atmosphere_____________?

• 1. Solubility
• 2. Viscosity
• 3. Porosity
• 4. Hygroscopicity

Question: The conduction of electricity, in semiconductors, takes place due to movement of______________?

• 1. positive ions only
• 2. negative ions only
• 3. positive and negative ions
• 4. electrons and holes

Question: Thermocouples are mainly used for the measurement of_____________?

• 1. temperature
• 2. resistance
• 3. eddy currents
• 4. coupling co-efficient

Question: Which of the following materials is the best conductor of electricity ?

• 1. Tungsten
• 2. Aluminium
• 3. Copper
• 4. Carbon

Question: Due to which of the following reasons copper and aluminium are not used for heating elements ?

• 1. Both have great tendency for oxidation
• 2. Both have low melting point
• 3. Very large length of wires will be required
• 4. All of the above

Question: Which of the following is a semiconductor material ?

• 1. Phosphorous
• 2. Rubber
• 3. Silicon
• 4. Aluminium