Question:
Consider a closed loop C in a magnetic field such that the flux passing through the loop is defined by choosing a surface whose edge coincides with the loop and using the formula φ= B1dA1 + B2dA2 + …. Now if we chose two different surfaces S1 and S2 having C as their edge, would we get the same answer for flux. Justify your answer.
Solution:
The magnetic flux lines passing through is the same as the magnetic flux lines passing through the surface. φ= B1dA1 + B2dA2 represents the magnetic field lines in an
area A with magnetic flux B. Therefore, the number of lines passing through S1 is the same as the lines passing through S2.