1. The problem statement, all variables and given/known data The radius of the orbit of an electron in a hydrogen atom is 0.05 nm. Using the planetary model, calculate the orbital velocity needed by the electron to avoid being pulled into the nucleus by electrostatic attraction. Round up your answer to the nearest tenth. 2. Relevant equations mv^2=k(e^2/r) mass of electron -13.6?? (not sure) v=velocity k= coloumb constant e=1.6x10^-19 3. The attempt at a solution 13.6(v^2)=k(q1q2/r2)(1.6x10^-19/5x10^11 m) i think the equation is wrong :( im not sure about coloumbs constant and what it is..