1. The problem statement, all variables and given/known data An α-particle accelerated between a pair of parallel plates in a vacuum tube acquires a kinetic energy of 103 eV. What is the potential difference between the plates? Answer: 500 V 2. The attempt at a solution Well, it's 1000 / 2 = 500 V because there are two plates. But I am not sure whether this is the right logic. Also KE = e * V. If we use this, we have (1000 * 1.6 * 10-19) J = 1.6 * 10-19 * V and so V = 1000 V. And not 500 V as in the answer. Is it correct to just divide 1000 by 2 and get 500 V and that is the answer in this case? Thanks in advance!