tolong dong nomor 21 dan 22

21) Dik : I = 3,6 A ; R1 = 6 ohm ; R2 dan R3 = 8 ohm
Dit : V?
Jawab:
* 1/R2&3 = 1/R2 + 1/R3
= 1/8 + 1/8 = 2/8
R2&3 = 8/2 = 4 ohm
* R total = R1 + R2&3
= 6 ohm + 4 ohm
= 10 ohm

V = I × R
V = 3,6 A × 10 ohm
V = 36 volt (B)

22) Dik :
1 mesin cuci 250 watt digunakan 2 jam/hari = 1 × 250 watt × 2 jam = 500 Wh
1 kulkas 65 watt digunakan 24 jam/hari = 1 × 65 watt × 24 jam = 1560 Wh
2 lampu bohlam 60 watt digunakan 8 jam/hari = 2 × 60 watt × 8 jam = 960 Wh
Total penggunaan listrik selama 1 hari = 500 + 1560 + 960 = 3020 Wh
Diubah ke kWh = 3020 / 1000 = 3,02 kWh
Dit : energi yang terpakai selama 30 hari
Jawab :
3,02 kWh × 30 = 90,6 kWh (C)