A uniform conducting wire of length is 24a, and resistance R is wound up as a current carrying coil in the shape of an equilateral triangle of side 'a' and then in the form of a square of side 'a'. The coil is connected to a voltage source V0. The ratio of magnetic moment of the coils in case of equilateral triangle to that for square is 1 : $\sqrt y$ where y is ................. .
Answer (integer)
3
Solution
In triangle shape ${N_t} = {{24a} \over {3a}} = 8$<br><br>In square ${N_s} = {{24a} \over {4a}} = 6$<br><br>${{{M_t}} \over {{M_3}}} = {{{N_t}I{A_t}} \over {{N_s}I{A_s}}}$ [I will be same in both]<br><br>$= {{8 \times {{\sqrt 3 } \over 4} \times {a^2}} \over {6 \times {a^2}}}$<br><br>${{{M_t}} \over {{M_s}}} = {1 \over {\sqrt 3 }}$<br><br>y = 3
About this question
Subject: Physics · Chapter: Magnetic Effects of Current · Topic: Biot-Savart Law
This question is part of PrepWiser's free JEE Main question bank. 96 more solved questions on Magnetic Effects of Current are available — start with the harder ones if your accuracy is >70%.