please Solve and show Why and how poynting vector is v rying

Last updated: 6/25/2023

please Solve and show Why and how poynting vector is v rying with time What realation is obtained How to get t he graph SOURCE NCERT EXEMPLAR 8 19 Poynting vectors S is defined as a vector whose magnitude is equal to the wave intensity and whose direction is along the direction of wave propogation Mathematically it is given by S ExB Show the nature of S vs t graph Ho