Physics-
General
Easy
Question
Two metallic rings A and B, identical in shape and size but having different resistivities 
and 
, are kept on top of two identical solenoids as shown in the figure. When current I is switched on in both the solenoids in identical manner, the rings A and B jump to heights hA and hB , respectively, with 
. The possible relation(s) between their resistivities and their masses 
and 
is(are)
and 
and
- and
- and
and
and
and
and
The correct answer is: and
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The figure shows certain wire segments joined together to form a coplanar loop. The loop is placed in a perpendicular magnetic field in the direction going into the plane of the figure. The magnitude of the field increases with time. 
and 
are the currents in the segments ab and cd. Then,
The figure shows certain wire segments joined together to form a coplanar loop. The loop is placed in a perpendicular magnetic field in the direction going into the plane of the figure. The magnitude of the field increases with time. and are the currents in the segments ab and cd. Then,
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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.
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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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chemistry-General
