question_answer 2)

A parallel plate capacitor (shown in figure)made of circular plates each of radius has a capacitance . Thecapacitor is connected to a 230 V a.c. supplywith a (angular) frequency of 300 rad . (a) What is the r.m.s. value of the conductioncurrent? (b) Is the conduction current equal to thedisplacement current? (c) Determine the amplitude of B at a point3.0 cm from the axis between the plates.  

Answer:

Here                                                 (a) Using  we get,                                                                 (b) Yes, because                                                 But                       (Conduction Current)                 (c) Consider the figure give below                 Using Ampere?s Circuital law we get                                 or                                             ?(i)                 But                                 where is the r.m.s. value of current                                  Amplitude,                 i.e.,