Before World War II, some radios got power through a resistance cord that had a
Chapter 21, Problem 11(choose chapter or problem)
Before World War II, some radios got power through a resistance cord that had a significant resistance. Such a resistance cord reduces the voltage to a desired level for the radios tubes and the like, and it saves the expense of a transformer. Explain why resistance cords become warm and waste energy when the radio is on.
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