Question

A copper wire is wound on a wooden frame, whose shape is that of an equilateral triangle. If the linear dimension of each side of the frame is increased by a factor of $3$, keeping the number of turns of the coil per unit length of the frame the same, then the self inductance of the coil?

• A. Decrease by a factor of $9\sqrt{3}$
• B. Increase by a factor of $3$
• C. Decreases by a factor of $9$
• D. Increases by a factor of $27$

Answer 1

Answer: (B)

Increase by a factor of $3$

Self inductance $\propto l$