1.不要被电压迷惑...做功=功率*时间=450w*60秒
2.p=u的平方/R=220*220/1210=40w .热量用上边公式40*60*10
3.p=热量/时间=6.6*10的4次方/60=1100w p=i的平方*r 1100=25*r r=44
1..做功=功率*时间=450w*60秒
2.p=u的平方/R=220*220/1210=40w .热量用上边公式40*60*10
3.p=热量/时间=6.6*10的4次方/60=1100w p=i的平方*r 1100=25*r r=44
1.W=Pt=450wX60s=27000J 2.P=U2/R=220VX220V/1210欧=40W W=Pt=40wX600s=24000J 3.P=W/t=66000J/60S=1100w w=I2Rt 所以R=W/I2t=66000J/(25A2X60S)=44欧
1、W=Pt=450W*60S=27000J
2、I=U/R=220V/1210欧=0.5A
P=UI=220V*0.5A=110W
Q=W=Pt=110W*600S=66000J
3、P=W/t=66000J/60S=1100W
P=UI U=P/I=1100W/5A=220V
R=U/I=220V/5A=44欧姆
1.t=1min=60s
Q=pt=450×60=27000J
2.P=U²/R=220²÷1210=40W
t=10min=600s
Q=Pt=40×600=24000J
3.t=1min=60s
P=Q/t=6.6×10四次方÷60=1.1×10三次方
P=I²R
R=P÷I²=1100÷25=44Ω