Keeping in mind that the electric potential decreases along the direction of the electric field and that change in particle's potential energy AU = qV, think about the following scenario: A proton (initial velocity v) moves against the electric field lines. This proton: A. speeds up B. slows downKeeping in mind that the electric potential decreases along the direction of the electric field and that change in particle's potential energy AU = qAV, think about the following scenario: A proton (initial velocity v) moves against the electric field lines. The kinetic energy of the proton: A. decreases B. increasesKeeping in mind that the electric potential decreases along the direction of the electric field and that change in particle's potential energy AU = qAV, think about the following scenario: A proton (initial velocity v) moves against the electric field lines. This proton: A. speeds up B. slows down