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________________?
(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 ?
(A) Copper
(B) Aluminium
(C) Steel reinforced copper
(D) Steel reinforced aluminium
A highly conductive material must have___________?
(A) highest conductivity
(B) lowest temperature co-efficient
(C) good mechanical strength
(D) good corrosion resistance
(D) easy solderable and drawable qualityF. all of the above
The metal having the lowest temperature coefficient of resistance is_________________?
(A) gold
(B) copper
(C) aluminium
(D) kanthal
The kinetic energy of a bounded electron is______________?
(A) less than that of unbounded electron
(B) greater than that of unbounded electron
(C) equal to that of unbounded electron
(D) infinite
(D) none of the above
Commonly used conducting materials are_____________?
(A) copper
(B) aluminium
(C) both (A) and (B)
(D) copper and silver
(D) platinum and gold
A perfect conductor has_____________?
(A) zero conductivity
(B) unity conductivity
(C) infinite conductivity
(D) none 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