Physics-
General
Easy
Question
A highly conducting ring of radius 
is perpendicular to and concentric with the axis of a long solenoid as shown in fig. The ring has a narrow gap of width 
in its circumference. The solenoid has cross sectional area 
and a uniform internal field of magnitude 
. Now beginning at 
, the solenoid current is steadily increased so that the field magnitude at any time 
is given by 
where 
. Assuming that no charge can flow across the gap, the end of ring which has excess of positive charge and the magnitude of induced e.m.f. in the ring are respectively
The correct answer is:
Since the current is increasing, so inward magnetic flux linked with the ring also increases (as viewed from left side). Hence induced current in the ring is anticlockwise, so end 
will be positive
Induced emf
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