25.3 A proton is released from rest at the positive plate of a parallel- plate capacitor. It crosses the capacitor and reaches the negative plate with a speed of 50,000 m/s. What will be the final speed of an electron released from rest at the negative plate?

25.5 What is the potential energy of the electron-proton interactions in FIGURE EX25.5? The electrons are fixed and cannot move.

Proton '0.50 nm Electrons 2.0 nm 10.50 nm FIGURE EX25.5