Một máy biến thế có số vòng cuộn sơ cấp là 2500 vòng, cuộn thứ cấp là 50000 vòng. Hiệu điện thế ở hai đầu cuộn thứ cấp là 25000V. a) Tính hiệu điện thế hai đầu cuộn sơ cấp. b) Điện trở đường dây tải điện là 150Ω, công suất cần truyền đi là 200kᴡ. Tính công suất hao phí trên đường dây truyền tải.

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