Answer
$\Delta K = 9.6\times 10^{-14}~J$
Work Step by Step
We can use conservation of energy to find the change in kinetic energy:
$K_2+U_2 = K_1+U_1$
$K_2- K_1 = U_1 - U_2$
$K_2- K_1 = V_1~q - V_2~q$
$K_2- K_1 = (V_1 - V_2)~q$
$\Delta K = (500.0~kV-200.0~kV)(2)(1.6\times 10^{-19}~C)$
$\Delta K = 9.6\times 10^{-14}~J$
