Electrical Installation and Maintenance (EIM) Practice Test 2025 - Free Electrical Maintenance Questions and Study Guide

The correct choice highlights the essential parameters for an incandescent bulb by focusing on rated current and rated voltage.

For an incandescent bulb, the rated voltage is crucial because it specifies the voltage at which the bulb is designed to operate efficiently. If the voltage exceeds the rated limit, it can cause the bulb to burn out, while operating below the rated voltage may result in reduced brightness and insufficient heating of the filament to produce light.

Rated current is equally important because it indicates the amount of current flowing through the bulb during normal operation. This parameter is directly related to the brightness of the bulb and its energy consumption. Each bulb is designed to operate at a specific current for optimal performance and longevity.

While rated power and rated resistance are relevant in the context of electrical devices, they derive from the rated voltage and rated current. For example, power is calculated using the product of current and voltage (P = IV) and resistance can be established using Ohm’s Law (R = V/I). Therefore, the most immediate and directly applicable parameters for the operation of an incandescent bulb are indeed rated current and rated voltage.