Physics-
General
Easy
Question
A small square loop wire of side
is placed inside a large squre loop of side
If the loops are coplanar and their centres coincide, the mutual induction of the system is directly proportional to
The correct answer is: 
Considering the larger loop to be made up of four rods each of length
, the field at the centre,
at a distance
from each rod, will be




So, the flux with smaller loop

and hence, 
or 
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