Page 50 - LISTRIK DINAMIS 1_Neat

KUNCI LATIHAN 4

1. Diketahui :  = 12 V; r = 1 ;
R = 5 ; t = 300 s

Ditanya : energi W pada beban R

Jawab : I = = = 2 A

2
2
W = I Rt = (2) (5) (300)
W = 6000 Joule

2. Diketahui : V = 12 Volt
R = 6

Ditanya : Daya P

Jawab : P = =

P = 24 Watt

3. Diketahui : P = 600 W;
V = 220 V
t = 8 h

Ditanya : Energi W .....

Jawab : P = W = P . t

W = (600 W) (8 h)
W = 4800 Wh
W = 4,8 kWh

4. Diketahui : P = 400 W ;
V = 220 V
m = 1 kg;
0
c = 4200 J / kg C
T = 100 – 20 = 80 C
0
Ditanya : t =

Jawab : P . t = m c T

t =

t = = 840 S

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