The value of critical field below the transition temperature will_______________?
A. increase
B. decrease
C. remain unchanged
D. any of the above
Electrical Engineering Materials
Superconductivity is observed for____________?
Superconductivity is observed for____________?
A. infrared frequencies
B. d.c. and low frequency
C. a.c. and high frequency
D. frequencies having no effect
E. none of the above
highest conductivity_____________?
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
High resistivity materials are used in_____________?
High resistivity materials are used in_____________?
A. precision instruments
B. heating elements
C. motor starters
D. incandescent lamps
E. all of the above
In a superconductor the value of critical density depends upon______________?
In a superconductor the value of critical density depends upon______________?
A. magnetic field strength
B. temperature
C. either (A) or (B)
D. both (A) and (B)
The conductivity of a conductor can be increased by_______________?
The conductivity of a conductor can be increased by_______________?
A. decreasing its temperature
B. increasing its temperature
C. decreasing its vibration
D. increasing its vibration
The superconductivity is due to____________?
The superconductivity is due to____________?
A. the crystal structure having no atomic vibration at 0°K
B. all electrons interact in the super-conducting state
C. the electrons jump into nucleus at 0°K
D. none of the above
Superconductors are becoming popular for use in________________?
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
Which of the following materials is preferred for transmitting electrical energy over long distance ?
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
A highly conductive material must have___________?
A highly conductive material must have___________?
A. 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