Question

A small positive electric charge is released at the midpoint between the two charged metal plates shown above. What will happen to the electric potential energy (EPE) of the charge?
A.
Its EPE would increase as it moves toward the negatively-charged plate.
B.
Its EPE would decrease as it moves toward the negatively-charged plate.
C.
Its EPE would increase as it moves toward the positively-charged plate.
D.
Its EPE would decrease as it moves toward the positively-charged plate.

Answer 1

B.

A positive test charge placed between oppositely charged plates is pushed by the electric field toward the negatively charged plate. The electric force does positive work on the charge, so its electric potential energy decreases (U = qV and V is lower near the negative plate).