The surface charge density on a hollow sphere of radius r is given by σ(θ) = v00 3r 15 cos2 θ − 4 , where v0 is a constant. find the potential inside and outside the sphere.

Consider two less-than-desirable options. in the first you are driving 30 mph and crash head-on into an identical car also going 30 mph. in the second option you are driving 30 mph and crash head-on into a stationary brick wall. in neither case does your car bounce off the thing it hits, and the collision time is the same in both cases. which of these two situations would result in the greatest impact force?