[tex]Dane:\\q_1 = q_2 = q\\W_1 = 20 \ J\\W_2 = 40 \ J\\Szukane:\\\frac{U_1}{U_2}=?\\\\\\U = \frac{W}{q}\\\\U_1 = \frac{W_1}{q} = \frac{20 \ J}{q}\\\\U_2 = \frac{W_2}{q} = \frac{40 \ J}{q}\\\\\frac{U_1}{U_2} = \frac{\frac{20 \ J}{q}}{\frac{40 \ J}{q}} = \frac{20 \ J}{40 \ J} =\frac{1}{2}\\\\\boxed{U_2 = 2U_1}[/tex]
