1.
[tex]dane:\\U = 14 \ V\\q = 2,5 \ MC = 2,5\cdot10^{6} \ C\\szukane:\\E_{el} = ?\\\\\\E_{el} = U\cdot I\cdot t\\\\ale \ \ q = I\cdot t, \ wiec\\\\E_{el} = U\cdot q\\\\E_{el} = 14 \ V\cdot2,5\cdot10^{6} \ C\\\\\underline{E_{e} = 35\cdot10^{6} \ J = 35 \ MJ}[/tex]
2.
[tex]dane:\\t = 3 \ 000 \ ms = 3 \ s\\I = 50 \ mA = 50\cdot10^{-3} \ A\\szukane:\\q = ?\\\\\\q = I\cdot t\\\\q = 50\cdot10^{-3} \ A\cdot3 \ s\\\\\underline{q = 150\cdot10^{-3} \ C = 150 \ mC}[/tex]
3.
[tex]dane:\\q = 48 \ Ah = 48 \ A\cdot3600 \ s = 172 \ 800 \ C\\t = 7 \ s\\I = 100 \ A\\szukane:\\\frac{q_1}{q} = ?\\\\\\q = I\cdot t\\\\q_1 = 100 \ A\cdot7 \ s = 700 \ C\\\\\underline{\frac{q_1}{q} = \frac{700 \ C}{172800 \ C} \cdot100\% \approx0,41\%}[/tex]