Jawaban:

Diket:

4 lampu, 10 watt, 12 jam/hari

1 setrika, 300 watt, 3 jam/hari

1 kulkas, 100 watt, 24 jam/hari

1 TV, 50 watt, 6 jam/hari

1 bulan = 30 hari

Biaya 1 kWh = Rp 1.000,-

Dit:

Biaya per bulan?

Penjelasan:

Energi dalam 1 hari

4 Lampu

⇒ W = 4 × W lampu

= 4 × P × t

= 4 × 10 × 12

= 480 Wh

1 setrika

⇒ W = P × t

= 300 × 3

= 900 Wh

1 kulkas

⇒ W = P × t

= 100 × 24

= 2.400 Wh

1 TV

⇒ W = P × t

= 50 × 6

= 300 Wh

Total energi 1 hari

= W 4 lampu + W setrika + W kulkas + W TV

= 480 + 900 + 2.400 + 300

= 4.080 Wh

= 4.080 ÷ 1.000 kWh

= 4,08 kWh

Total energi sebulan

= total energi sehari × jumlah hari dalam sebulan

= 4,08 × 30

= 122,4 kWh

Biaya = harga 1 kWh × total energi sebulan

= 1.000 × 122,4

= 122.400 rupiah