Question

A copper wire is wound on wooden frame whose shape is equitlateral triangle if the linear dimensions of the each side of frame is increased by a factor of 3 keeping number of turns per unit length of coil same then the self inductance of the coil

Answer 1

Answer:

According to the problem the wire is wound on wooden frame having shape like equilateral triangle

let the  length of each side is a

then the total length,l is 3a

therefore the area, A= √ 3/4 a^2

Let the diameter of the wire  is r

Therefore the self inductance= μ0n^2Al=μ0n^2(√ 3/4 a^2)dN where N is the number of turns.

Therefore the self inductance increases 3 times