(1)I=U/R=6V/10欧=0.6A
W=UIt=6V*0.6A*60s=216J
(2)P=W/t={3.6*10(6)}/25h=0.04kW=40W
R=U(2)/P=220(2)V/40W=1210欧
注意()内为次方