CompTIA Network+ Practice Test

What is a common cause of brownouts?

1. Electrical equipment failure

2. Sudden increase in line voltage

3. Significant fall in power supply

4. Overloading circuits

The correct answer is: Significant fall in power supply

A common cause of brownouts is a significant fall in power supply. Brownouts occur when there is a temporary drop in voltage in an electrical power supply system. This can happen for various reasons, but it often results from a lack of supply to meet the demand for electricity in a given area. When the demand exceeds the available supply, the utility company may intentionally reduce voltage levels to stabilize the system and prevent complete blackouts. This situation is frequently seen during peak usage times when the demand for electricity is at its highest, causing the available power supply to drop. It is important to understand that brownouts may also be a tactic employed by power companies to manage excessive load on the grid and is a sign that the infrastructure may be strained. In contrast, options related to electrical equipment failure or overloading circuits may cause disruptions or outages in a localized area, but they do not inherently result in the voltage drop characteristic of brownouts. A sudden increase in line voltage would not cause a brownout, as that reflects an increase in electric supply rather than a reduction.