Question1

A hemispherical shell (half-sphere like a bowl) of radius a = 30 cm, centered at the origin (i.e. the same center as the full sphere would have), has a surface charge density of = ()/(). This half-sphere covers / and . [The charges on this surface are negative]. a. Determine the electrostatic potential at the center of this hemisphere (in volts). b. What speed does an electron ( = . ; = .1 x10 ) reach if you release it from the original rest? [The electron will experience a repulsive electrostatic force and accelerate towards infinity. We are asks to determine its speed when it reaches infinity. Suppose the only force acting on the electron is this electrostatic force. [Hint: kinetic energy =(/)]].

Question 2

Imagine a conductive metallic sphere of radius a = 2 cm carrying a total charge Q_a = 8 nC (8x10^-9 C) evenly distributed over its surface. A concentric spherical shell of radius b = 3 cm carries a load total Qb = -8 nC. The central sphere and the other shell are centered at the origin.

a. What is the electrostatic potential difference of a point located at (0.0.2) cm from the potential at the point (3,3,0) cm? [Please note that these points are expressed in rectangular coordinates, so which you should probably work in spherical coordinates when doing your calculations] b. What is the electrostatic potential difference of a point located at (0.0.2) cm from the potential at the point (8,0,0) cm? [Please note that these points are expressed in rectangular coordinates, so which you should probably work in spherical coordinates when doing your calculations]