Two electrons in an atom are separated by 1.5 × 10−10 m, the typical size of an atom. What is the force between them? The Coulomb constant is 9×10 N·m /C . Answer in units of N.

(a) assume the equation x = at^3 + bt describes the motion of a particular object, with x having the dimension of length and t having the dimension of time. determine the dimensions of the constants a and b. (use the following as necessary: l and t, where l is the unit of length and t is the unit of time.) (b) determine the dimensions of the derivative dx/dt = 3at^2 + b. (use the following as necessary: l and t, where l is the unit of length and t is the unit of time.)