The two main expressions for power dissipation P in Ohmic conductors, namely and , typically confuse students about why high voltage V should be preferred to high current I when transmitting electrical power through the National Grid. Here we suggest that such misconceptions can be avoided if students are encouraged to focus on the delivery of useful power (transmission efficiency), rather than energy losses.

中文翻译：

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澄清有关电网电力传输中欧姆定律和功率耗散的误解

欧姆导体中功率耗散P的两个主要表达式，即和，通常会使学生混淆，为什么在通过国家电网传输电力时应该优先选择高电压V 而不是高电流I。在这里，我们建议，如果鼓励学生专注于提供有用的功率（传输效率），而不是能量损失，就可以避免这种误解。