Extra exam question E7D10

WhyA switching power supply is less expensive and lighter than an equivalent linear supply because its high-frequency inverter design uses much smaller transformers and filter components. A switching power supply's high-frequency inverter design lets it use much smaller transformers and filter components than an equivalent linear supply needs, since transformer and filter component size scales down as operating frequency goes up, directly reducing cost and weight, answer C. It still requires an output filter, control circuitry current draw isn't the reason for the size and cost difference, and it doesn't recover power from an unused portion of the AC cycle, that's not how a switching supply actually achieves its efficiency and size advantages.