1. The problem statement, all variables and given/known data An electron moving with a speed v can behave as wave with wavelength 6.4 x 10^-15 m. Given that the mass of electron = 9.1 x 10^-31 kg and the charge of electron is 1.6 x 10^-19 C, find (a) the speed of v of the electron, and (b) the voltage needed to accelerate the electron from rest until it acquires the speed v. 2. Relevant equations 3. The attempt at a solution (a) wavelength = h / mv v = h/ (m x wavelength) = 1.1384 X 10^11 m/s How do I calculate (b)? Please help, thank you. Kindly correct me if (a) is wrong.