Question

Figure shows a conducting loop in shape of a trapezium carrying current i= 10A . Find the magnetic field B at point P. It's is given that a = 10cm​

Answer 1

Answer: The correct answer is 5.

Given: A trapezium loop with current (i)= 10A, a = 10cm

To find: Magnetic field (b) at point(p).

Solution:

     űǒi

B1= ------ ( sinϴ1 + sinϴ2)

    4πd                                          űǒi

B2= ------(sin30° + sin30°) =   --------  (1)   (k^n)

       4πa                                     4πa

          Űǒi                     űǒi

B3= -----------(1)  = ------------ (-k^n)

         4π(2a)              8πa

B= B1 + B2

     űǒi               űǒi

 = ------  -     ----------

    4πa              8πa

     10^(-7)       100

=   ----------  x   ------

         2                1

  =50 x 10^(-7) T  

  = 5micro T

So, the magnetic field at point(P) is 5 micro T