31. |
Superconductors are used for
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Answer:
Option (a) |
32. |
A small size relay or switch made of superconductors.
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Answer:
Option (b) |
33. |
The following is the first London equation
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Answer:
Option (d) |
34. |
The following is the second London equation
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Answer:
Option (a) |
35. |
The penetration depth is the __________ where the current drops to 1/e times of its value at the surface.
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Answer:
Option (d) |
36. |
For mercury of mass number 202, is 4.2 K. Find the transition temperature for its isotope of mass number 200.
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Answer:
Option (b) |
37. |
The critical temperature for a metal with isotopic mass 199.5 is 4.185 K. Calculate the isotopic mass if the critical temperature falls to 4.133 K
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Answer:
Option (d) |
38. |
A superconductor tin has a critical temperature of 3.7 K in zero magnetic field and a critical field of 0.0306 T at 0 K. Find the critical field at 2 K.
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Answer:
Option (b) |
39. |
Calculate the critical current through a long thin superconducting wire of radius 0.5 mm. The critical magnetic field is 7.2 kA/m
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Answer:
Option (a) |