Physics-
General
Easy
Question
Statement -1 A vertical iron rod has a coil of wire wound over it at the bottom end. An alternating current flows in the coil. The rod goes through a conducting ring as shown in the figure. The ring can float at a certain height above the coil.
Statement - 2 In the above situation, a current is induced in the ring which interacts with the horizontal component of the magnetic field to produce an average force in the upward direction
- Statement-1 is True, Statement-2 is True; Statement-2 is a correct explanation for Statement-1
- Statement-1 is True, Statement-2 is True; Statement-2 is NOT a correct explanation for Statement-1
- Statement-1 is True, Statement-2 is False
- Statement-1 is False, Statement-2 is True.
The correct answer is: Statement-1 is True, Statement-2 is True; Statement-2 is a correct explanation for Statement-1
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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
A superconductor has (0) = 100 K. When a magnetic field of 7.5 Tesla is applied, its decreases to 75 K. For this material one can definitely say that when :
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
A superconductor has (0) = 100 K. When a magnetic field of 7.5 Tesla is applied, its decreases to 75 K. For this material one can definitely say that when :
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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
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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?
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The capacitor of capacitance C can be charged (with the help of a resistance R) by a voltage source V, by closing switch 
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The capacitor of capacitance C can be charged (with the help of a resistance R) by a voltage source V, by closing switch while keeping switch open. The capacitor can be connected in series with an inductor ‘L’ by closing switch and opening .
After the capacitor gets fully charged, is opened and is closed so that the inductor is connected in series with the capacitor. Then,
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The capacitor of capacitance C can be charged (with the help of a resistance R) by a voltage source V, by closing switch while keeping switch open. The capacitor can be connected in series with an inductor ‘L’ by closing switch and opening .
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The capacitor of capacitance C can be charged (with the help of a resistance R) by a voltage source V, by closing switch while keeping switch open. The capacitor can be connected in series with an inductor ‘L’ by closing switch and opening .
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=150)
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