Answer: A continuous visible spectrum is produced by an incandescent lightbulb.
According to physics teachers, visible light spectrum refers to the range of wavelengths that the human eye can discern. The vast majority of electromagnetic waves, however, are invisible to the human eye. Below is a graph that compares the visible spectrum with the whole electromagnetic spectrum.
An incandescent lamp uses electricity to light its source. The lamp’s mechanism is based on heating a tungsten filament to produce light. While Thomas Edison is well-known for inventing the incandescent lamp and being the inventor of it, Joseph Wilson Swan was the first to patent the mechanism.
Warm substances produce the continuous type of visible spectrum. The sun, for example, emits a continuous visible spectrum. The electromagnetic radiation spectrum is continuous because of the way the incandescent lamp is lit.