Question

only part C

Bext 2. A single circular loop of wire is exposed to an external magnetic field Bext pointing into the page. (a) The magnetic flux through the loop is initially 0.076 Wb, and the loop's radius is 27.5 cm. Calculate Bext, the magnitude of the external magnetic field. For a circle: A = Ttr?. xxxx (b) Calculate the magnitude of the emf induced in the loop when the external magnetic flux increases from 0.076 Wb to 0.091 Wb in 6.0 ms (milliseconds). (c) Starting with the external magnetic flux, deduce the direction of the induced magnetic field Bind inside the loop, and then the direction of the induced current lind in the loop as the external flux increases. Explain each step of your deduction without mention of either RHR. xxx xxxx

Answer 1

Bext. The x X x x X X x d. external magnetic field, Bext. is pointing inward to the plane of : papesi According to Lenz's law an induced emif. is produced in the loop due to change of & magnetic flux. This emif. produces a current in the loop (find). Further this induced current produces an Induced magnetic field (Bindhich will oppose the change in flux. . So, Bind should be in the outward direction of the plane of papes as the external field, Bext. increases in the inward direction. Now, according to right hand thumb sale if we point our thumb along the direction of cursent flow and curl our othes four fingers, then the curled fingers will show the direction of magnetic lines of forces due to the current flow.

So, in this circular current carrying loop if the cursent flows in anti-clockwise direction the induced magnetic field will be in outward direction of the plane of paper. So, I ind flows in anti-clockwise direction and Bind is in outward to the plane of papes.
Please note that the induced magnetic field only at the central line of the loop is always outwards to the plane of paper.