a, Uđm= Uab= 220 V
=> P=Pđm =1000 W
\(A=P\cdot t=1000\cdot10=10000\left(Wh\right)\)
b,\(R=\dfrac{U_{đm}^2}{P_{đm}}=\dfrac{220^2}{1000}=48,4\left(\Omega\right)\)
\(P=\dfrac{U^2}{R}=\dfrac{210^2}{48,4}\approx911,15\left(W\right)\)
\(A=P\cdot t=911,15\cdot10=9111,5\left(Wh\right)\)