Предмет: Физика, автор: Dashaant

Медный провод длиной 5 км имеет сопротивление 12Ом. определить массу меди, необходимой для его изготовления.

Развернутое решение, пожалуйста

Ответы

Автор ответа: константиновна

m=V/ρ, где ρ-плотность меди ( таблице)

V=S·l

R-ρ₀l/s, где ρ₀-удельное сопротивление меди⇒s= ρ₀l/R

V=ρ₀l/R·l=ρ₀l²/R

m=ρ₀l²/Rρ

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Медный провод длиной 5 км имеет сопротивление 12Ом. определить массу меди, необходимой для его изготовления. Развернутое решение, пожалуйста

Ответы

Медный провод длиной 5 км имеет сопротивление 12Ом. определить массу меди, необходимой для его изготовления.

Развернутое решение, пожалуйста