The energy the electron gives up passing between the electrodes is equal to the product between its charge and the potential difference between the electrodes:
![\Delta U = e \Delta V](https://img.qammunity.org/2019/formulas/physics/high-school/fjq3pf659ivh5o8ft747lb6nh2rdlxhptr.png)
where
e is the electron charge
![\Delta V](https://img.qammunity.org/2019/formulas/physics/high-school/x1qy9bfx3cpvdd1hmryo40y93wbocai2gp.png)
is the potential difference
Plugging numbers into the equation, we find that the electron gives up is
![\Delta U = (1.6 \cdot 10^(-19) C)(14700 V)=2.35 \cdot 10^(-15) J](https://img.qammunity.org/2019/formulas/physics/high-school/g890mk7fczm2ta7bjo0ygexq8oinjel377.png)