Final answer:
The vacuum pump is considered the most essential element besides the carbon-filament light bulb in Edison's light bulb, as it helped to create and maintain the vacuum essential for the bulb's efficiency and longevity.
Step-by-step explanation:
Besides the carbon-filament light bulb, the most essential element of Edison's light would be considered the vacuum pump. The use of a vacuum pump was crucial in the early years of light bulbs, as it served to partially evacuate the bulbs. This reduction in air pressure was key to minimizing heat loss through conduction, keeping the filament hot with less energy and preventing the filament from burning by removing oxygen. Furthermore, the vacuum inside the bulb prevents tungsten atoms, which evaporate at high temperatures, from oxidizing, allowing them to return to the filament and extend the bulb's lifespan.
The most essential element of Edison's lightbulb, besides the carbon-filament, would be the glass bulb. The glass bulb plays a crucial role in the functioning of the lightbulb by housing the filament and creating a partially evacuated environment. The glass bulb is necessary to protect the filament and prevent it from oxidizing. Additionally, the vacuum created within the glass bulb helps to minimize heat conduction to the exterior, allowing the filament to reach the high temperatures needed for the emission of light.