[tex]dane:\\R = 2 \ k\Omega = 2 \ 000 \ \Omega\\I = 2 \ mA = 0,002 \ A\\t = 20 \ s\\szukane:\\W = ?\\\\Rozwiazanie\\\\W=U\cdot I\cdot t\\\\ale \ \ U = I\cdot R, \ zatem:\\\\W = I^{2}\cdot R\cdot t\\\\W = (0,002 \ A)^{2}\cdot2 000 \ \Omega\cdot20 \ s\\\\W = 0,16 \ J[/tex]
