Question

Answer 1

a. \(\left\{{}\begin{matrix}R=\dfrac{U^2}{P}=\dfrac{220^2}{800}=60,5\Omega\\I=\dfrac{P}{U}=\dfrac{800}{220}=\dfrac{40}{11}A\end{matrix}\right.\)

b. \(R=p\dfrac{l}{S}\Rightarrow l=\dfrac{RS}{p}=\dfrac{110\cdot0,02\cdot10^{-6}}{0,40\cdot10^{-6}}=5,5m\)

c. \(A=Pt=800\cdot\dfrac{30}{60}=400\)Wh

d. \(A'=Pt=800\cdot2\cdot31=49600\)Wh = 49,6kWh

\(\Rightarrow T=A'\cdot1500=49,6\cdot1500=74400\left(dong\right)\)