Предмет: Физика, автор: ilatkac367

Визнач густину сплаву міді та цинку, якщо об'єм міді втричі більший за об'єм цинку. Густина міді становить 8900кг/м, а густина цинку 7100кг/м

Ответы

Автор ответа: ninjazhanibek

m₁,V₁,ρ₁- мідь, m₂,V₂,ρ₂- цинк m,V,ρ- сплав V₁=3V₂

ρ=m/V=(m₁+m₂)/(V₁+V₂)=(ρ₁V₁+ρ₂V₂)/(3V₂+V₂)=(3ρ₁V₂+ρ₂V₂)/(4V₂)=

=(3V₂(ρ₁+ρ₂))/(4V₂)=3(ρ₁+ρ₂)/4=0.75(ρ₁+ρ₂)=0.75×(7100+8900)=12000

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