Physics-
General
Easy
Question
A vertical conducting ring of radius R falls vertically with a speed V in a horizontal uniform magnetic field B which is perpendicular to the plane of the ring :
- A and B are at same potential
- C and D are at same potential
- current flows in clockwise direction
- current flows in anticlockwise direction
The correct answer is: C and D are at same potential
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Electrical resistance of certain materials, known as superconductors, changes abruptly from a nonzero value to zero as their temperature is lowered below a critical temperature (0). An interesting property of superconductors is that their critical temperature becomes smaller than (0) if they are placed in a magnetic field, i.e., the critical temperature (B) is a function of the magnetic field strength B. The dependence of (B) on B is shown in the figure
In the graphs below, the resistance R of a superconductor is shown as a function of its temperature T for two different magnetic fields 
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Electrical resistance of certain materials, known as superconductors, changes abruptly from a nonzero value to zero as their temperature is lowered below a critical temperature (0). An interesting property of superconductors is that their critical temperature becomes smaller than (0) if they are placed in a magnetic field, i.e., the critical temperature (B) is a function of the magnetic field strength B. The dependence of (B) on B is shown in the figure
In the graphs below, the resistance R of a superconductor is shown as a function of its temperature T for two different magnetic fields (solid line) and (dashed line). If is larger than , which of the following graphs shows the correct variation of R with T in these fields?
physics-General
