Aspherical shell of radius r centered at the origin carries a uniform surface charge density σ, corresponding to a total charge q 4π r2σ. for a point at distance z from its center, calculate the electric field strength. note: you must treat the two cases, z r separately. it may be to use the law of cosines to define the separation of source and field points, s = v 2 : 2 rzoost. you might express the answers in terins of q are the results what you expected?