Penjelasan:

17. hukum kircoff I

Sigma(I)keluar=Sigma(II)masuk

I(1)=I(2)+I(3)

hukum kircoff II

• Loop I

Sigma(E)+Sigma(IR)=0

-8+I(1)×2+I(3)×6=0

2I(1)+6I(3)=8

• Loop II

Sigma(E)+Sigma(IR)=0

18+2I(2)-6I(3)=0

2I(2)-6I(3)= -18

2( I(2)+I(3))+6I(3)=8

2I(2)+8I(3)=8

2I(2)-6I(3)= -18 -

------------------------

14I(3)=26

I(3)= 13/7

2I(2)-78/7 = -18

2I(2) = 78/7 -18

I(2) = -48/14

I(2)= -3,43 A

Tanda minus menunjukkan arah, besar I(2) adalah 3,43

18. Energi listrik Lampu A

=P×t=30×12=360= 0,36 kWh

Energi listrik Lampu B

=P×t=40×12= 480= 0,48 kWh

Energi listrik Lampu C

= P×t= 50×15= 0,75 Kwh

Energi listrik televisi

= P×t=150×12=3000=3 kWh

Energi listrik kulkas

= P×t= 120×24=2880= 2,88 kWh

Energi listrik Mesin cuci

=P×t= 100×2 = 0,2 kWh

Total biaya yang harus fi bayar;

30×500×7,67 = 115.050