Television antennas often have one or more horizontal metal bars mounted behind the receiving antenna and insulated from it, as shown in Figure 24.124. Explain qualitatively why adding a second metal...

Television antennas often have one or more horizontal metal bars mounted behind the receiving antenna and insulated from it, as shown in Figure 24.124. Explain qualitatively why adding a second metal bar can make the television signal either stronger or weaker, depending on the distance between the front receiving antenna and the second bar