Bantu dong nomor 21-23

Jawaban:

21. W = VIt

W = 100 volt x 5 ampere x 60 detik = 30000 J

22. W = VIt = IR It

Hambatan pengganti

1/Rp = 1/6 + 1/8 = 4/24+3/24 = 7/24

Rp = 24/7

Vp = IRp = 1 x 24/7 = 24/7 volt

krn paralel, tegangan pada 6 dan 8 ohm = Vp = 24/7 volt

arus pd hambatan 6 ohm,

I = V/R = 24/7  / 6 = 4/7 A

arus pd hambatan 8 ohm

I = 24/7  /8 = 3/7 A

maka energi pda hambatan 6 ohm

W = IRIt = 4/7 x 6 x 4/7 x 7 = 13,7 J

energi pd hambatan 8 ohm

W = 3/7 x 8 x 3/7 x 7 = 10,3 J

23.

ΣE + ΣIR = 0

-E1 + IR1 + E2 + IR2 + IR3 = 0  

-6 + 3I +3 + 2I + I = 0

-3 + 6I = 0

I = 0,5

a. P = VI  

P1 = 6 x 0,5 = 3 watt

P2 = 3 x 0,5 = 1,5 watt

b. P = VI = IR I

P1 = 0,5 x 3 x 0,5 = 0,75 watt

P2 = 0,5 x 2 x 0,5 = 0,5 watt

P3 = 0,5 x 1 x 0,5 = 0,25 watt

Penjelasan: