Một máy biến thế có só vòng dây ở cuộn sơ cấp là 1000 vòng, cuộn thứ cấp là 2500 vòng. Cuộn sơ cấp nối vào nguồn điện xoay chiều có hiệu điện thế 110V. Tính hiệu điẹne thế hiệu dụng ở hai đầu cuộn thứ cấp? Gíup e với ạ!

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