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Which of the following is the correct representation of the electric field created by two positive charges? You do NOT need to show your work or explain your reasoning in this problem.  

A small plastic sphere has a mass of 0.42 g and a charge of -51 nC. It is 10.0 cm directly above an identical sphere that is charged to -36 nC. This lower sphere is fixed and cannot move. If the upper sphere is released, what is the magnitude of its initial acceleration? Show all of your work. 

Both a plane mirror and a sheet of paper are flat and feel fairly smooth, yet you can see your reflection in a mirror but not in a sheet of paper. Select which statement or statements are TRUE. You do NOT need to show or explain your work for this problem.

In the previous question with the circular loop, if the loop’s resistance is 0.15 Ω, what is the value of the induced current? Show all of your work.

In the previous question, what is the direction of the net electric force on the 1.0 nC charge at the bottom of the figure? [answer]

A thin layer of water is spread on top of a sheet of glass. A light ray in the air is incident on the water 25° from the surface of the water. What is the ray’s angle (in degrees) from the normal after entering the glass? Show all of your work.

    A straight wire is causing a magnetic field, as shown. (The magnetic field circles the wire in a clockwise motion as viewed from the top.) What is the direction of the current? You do NOT need to show your work or explain your reasoning.

The currents through several segments of a wire object are shown. What are the magnitudes of the currents in segments B and C? Show or explain how you arrived at your answer.   The current is wire segment B is [ansB] and the current in wire segment C is [ansC]. 

    What is the size of the net electric force on the 1.0 nC charge at the bottom of the figure? Show all of your work on your paper.

    A metal rod A and a metal sphere B, on insulating stands, touch each other as shown. They are originally neutral. First, a positively charged rod is brought near (but not touching) the far end of A. Then, while the charged rod is still close, A and B are separated. Finally, the charged rod is then withdrawn.   At the end, the charge on the rod and sphere are _______________. You do NOT need to show your work or explain your reasoning.