(1):P=UI=2V×0.2A=0.4W;
(2):R2=(U总-U1)/I=(6V-2V)/0.2A=20Ω P发热=I²R=0.2²×20Ω=0.8W;
(3):R1=U/I=2V/0.2A=10Ω I=U/R1=6V/10Ω=0.6A P=UI=6V×0.6A=3.6W.
(1):P=UI=2V×0.2A=0.4W;
(2):R2=(U总-U1)/I=(6V-2V)/0.2A=20Ω P发热=I²R=0.2²×20Ω=0.8W;
(3):R1=U/I=2V/0.2A=10Ω I=U/R1=6V/10Ω=0.6A P=UI=6V×0.6A=3.6W.