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ntthainganqn
2 năm trước
Một điện tích chuyển động trong điện trường theo một đường cong kín. Gọi công của lực điện trong chuyển động đó là A thì A.A > 0 nếu q > 0. B. A > 0 nếu q < 0. C. A > 0 nếu q < 0. D. A = 0. Giải thích đầy đủ, tiện cho mình hỏi đường cong kín là điện trường như thế nào
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