Final answer:
A negative charge accelerates in a region where the electric potential is increasing, due to its attraction towards less negative potential regions.
Step-by-step explanation:
A negative charge speeds up in a region of space where the electric potential is increasing. This is because a negative charge is repelled from regions of lower (more negative) potential and attracted towards regions of higher (less negative) potential. The phenomena illustrate that the electrostatic forces on particles like electrons are generally much stronger than gravitational forces. When considering electron acceleration, the small mass of electrons makes it easy for even small voltages to accelerate them to high speeds. In applications like electron guns, voltages often exceed 100 V, but at lower voltages, as used in this example, the gravitational force can be considered negligible, and relativistic effects are not taken into account.