Thị Bé

Trên cùng một đường dây tải điện , nếu dùng máy biến thế để tăng hiệu điện thế ở 2 đầu dây dẫn lên 100 lần thì công suất hào phí vì tỏa nhiệt trên đường dây sẽ giảm đi bao nhiêu lần? ( giải chi tiết dùm ming với ạ. Hứa đánh giá 5 sao ?

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Tun Bé

Đáp án:Php = ( $P^{2}$ .R)/ $U^{2}$
Do đó $P_{h p}$ tỉ lệ nghịch với $U^{2}$ nên U tăng 100 lần thì $P_{h p}$ giảm $100^{2}$ = 10 000 lầ

Giải thích các bước giải:

songuyen05

2 năm trước

Đáp án:

Giải thích các bước giải:

Ta có Php = ($P^2$.R)/$U^2$
Do đó $P_{hp}$ tỉ lệ nghịch với $U^2$ nên U tăng 100 lần thì $P_{hp}$ giảm $100^2$ = 10 000 lần

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