Chapter 18, Problem 2P

* A uranium nucleus has 92 protons. (a) Determine the magnitude of the $\stackrel{\to }{E}$ field at a distance of $\text{0}{\text{.58×10}}^{\text{-12}}\text{m}$ from the nucleus (about the radius of the innermost electron orbit around the nucleus). (b) What is the magnitude of the force exerted on an electron by this $\stackrel{\to }{E}$ field? (c) What assumptions did you make? If the assumptions are not valid, will the magnitude in part (b) be an overestimate or underestimate of the actual value?

Draw a force diagram (a) for a bag hanging at rest from a spring; (b) for the same bag sitting on a table; and (c) for the same bag that you start to lift so it moves up faster and faster.