Question

.1.Positive charge Q is distributed uniformly along the z-axis from x = 0 to x = a. A positive point charge q is located on he positive z-axis at a distance d to the right of the origin.

(a) Calculate the electric potential produced by the charge distribution Q at x = d. 

(b) Develop an expression for the potential energy that would be added to the system by bringing a charge q from infinity to x = d. 

(c) Assuming the charges Q and q are of the same sign (so that repulsion occurs), develop an expression for the speed that charge q would be moving at after being released from x = d and moving very far away. (Consider the mass of charge q to be m) 

(d) Your instructor will show (using a Taylor series) that if d≥a, the magnitude of the electric potential from part (a) is the same as that generated by a point charge. 

2. The electric field at the surface of a charged, solid, copper sphere with radius 0.200 m is 3800 N/C, directed toward the center of the sphere. Consider the zero point for potential to be at infinity. 

(a) What is the potential at the surface of the sphere? 

(b) What is the potential at a distance of 0.100 m from the center of the sphere? 

(c) What is the potential at a distance of 0.100 m from the surface of the sphere? 

(d) Why do we care what the potential generated by the sphere is at different locations in space?

Answer 1