PHYS 122 Midterm: Phys122Fall2014Exam2MCSolutions
Document Summary
The particle is negatively charged, and so it feels an electric force opposite the electric field. Since the electric force on it is to the right, the electric field must be to the left, hence (i) is true. The particle also, generally, feels a force in the direction of decreasing potential energy, hence (ii) is true as well. Since the particle is negatively charged, a decrease in its electric potential energy corresponds to an increase in the electric potential, hence (iii) is false. The potentials of each point charge at the origin add (as scalars) to the total potential: The electric field did positive work, of an amount: The new capacitor is equivalent to two capacitors in series: the first being a parallel plate capacitor of spacing 3d/4 filled with the dielectric (hence with. ) and the second with spacing d/4 (with capacitance.
