A line spectrum and a continuous spectrum are two different types of spectral emissions that arise from different physical processes.
A line spectrum, also known as a discrete spectrum, consists of specific wavelengths of light emitted by atoms or molecules as they transition between energy levels. When an electron in an atom absorbs energy, it can jump to a higher energy level. When it returns to its original state, it releases energy in the form of light, resulting in bright lines at certain wavelengths corresponding to the energy differences between the levels. These lines appear as distinct colors on a dark background, and each element has a unique line spectrum, acting like a fingerprint.
On the other hand, a continuous spectrum contains all wavelengths of light within a given range, appearing as a seamless gradient of colors without distinct lines. This type of spectrum is emitted by solid, liquid, or densely packed gases when they are heated, as they radiate energy across a broad range of wavelengths. An example of a continuous spectrum is the light emitted from a traditional light bulb, which produces a smooth transition of colors.
In summary, the key difference lies in their formation: a line spectrum consists of individual lines corresponding to specific energy transitions of electrons in atoms, while a continuous spectrum contains a full range of wavelengths and is typically produced by hot objects or materials. Understanding this distinction is fundamental in fields like spectroscopy, helping to identify the composition of various substances based on their emitted light.