1. The problem statement, all variables and given/known data Two 4.0 cm diameter disks face each other, 2.0 mm apart. They are charged to +-12 Nc. Part A What is the electric field strength between the disks? E = 1.1 * 10^6 N/C Part B A proton is shot from the negative disk toward the positive disk. What launch speed must the proton have to just barely reach the positive disk? 2. Relevant equations E=(Q/(epsilon zero * A) v=x/t 3. The attempt at a solution I was able to figure out part A. I just need help with part B. V = ? x = 2mm t = ? Doesn't seem like this part should be difficult, so I must be missing something simple... Thanks in advance for any help.