Question

two identical wires A and B each of length L carry the same current I . wire A is bent into a circle of radius R and wire B is bent to form a square of side . if Ba and Bb are the value of magnetic field at the centers of a circle and square respectively , then the ratio Ba/Bb is

a => π²/8

b => π²/16√2

c=> π²/16

d => π²/8√2

Answer 1

hope it can help you please mark me as brainliest.

Answer 2

Hello pari : -) 

magnetic field in case of circle of radius R we have as see the photo  I made for you in the paint you will get the mindset to solve this question ! 

Ba = > U ° I / 2R   

as 2πR = > L    here L = > length of wire 

R = > L / 2π 

now we put the value of R in U ° I / 2R    

Ba = > U°I / ( 2 × L/2)   = >  U°I π  / L 

magnetic field in case f square of side a we get 

Bb = >  4 ×U°/4π  ×   I /a/2  ( 1/√2   + 1/√2 )  which means 

Bb = >4IU°/πa√2   = > U°2√2 I /aπ 

4a = > L  we get a = > L/4  = >  Bb = > 8√2 U°I /πL

dividing Ba/Bb we get  π²/8√2 

hopes this helps you 

@ engineer gopal khandelwal b-tech IIT ROORKEY !