✔ 最佳答案
第3題
1. R1 + R3 = 6Ω + 3Ω = 9Ω
2. I = V / R = 36V / 9Ω = 4A
3. VR3 = V = I R = 4A * 3Ω = 12V
4. R2 + R4 = 16Ω + 4Ω = 20Ω
5. I = V / R = 36V / 20Ω = 1.8A
6. VR4 = V = I R = 1.8A * 4Ω = 7.2V
a & b = 12V - 7.2V = 4.8V
第4題
R2 + R3 +R4 = 100Ω + 120Ω + 100Ω = 320Ω
Rt = 1/(1/R1 + 1/R2)
= (1/300) + (1/320)
= 1 / 0.003333 + 0.003125
= 1 / 0.006458
= 154.846Ω
= 155Ω
I = 300mA - 200mA = 100mA
V = 100mA * 155Ω = 15.5V
R1 = V / R = 15.5V / 300Ω = 0.05166A = 51.66mA
第5題
睇唔清楚, 無法作答。
如果再有人話我既解答9唔答8, 呢題叫佢作答。
2011-03-27 18:52:00 補充:
希望唔係作業
2011-03-27 18:57:11 補充:
http://hk.knowledge.yahoo.com/question/question?qid=7011032001432