Light Sources - Natural Light Sources, Artificial Light Sources, FAQs

Everything that we observe in our surroundings is a result of light. Human eyes are sensitive to between 390 and 700 NM, which is a specific frequency of electromagnetic radiation, also known as light. Even when we focus on a single leaf, we are already aware of its green colour since light reflects off of it and reaches our eyes, indicating its colour. In this article, we will be studying types of light, sources of light, natural sources of light, artificial sources of light, light source, what is a light source, artificial light, point source of light, and examples of natural sources of light.

JEE Main 2025: Physics Formula | Study Materials | High Scoring Topics | Preparation Guide

JEE Main 2025: Syllabus | Sample Papers | Mock Tests | PYQs | Study Plan 100 Days

NEET 2025: Syllabus | High Scoring Topics | PYQs

What is Light?

Light exhibits a dual nature. It shows the properties of both waves and particles. According to wave theory, light is made up of a bundle of electromagnetic fields that carry a specific amount of energy.

According to particle theory, light is made up of particles called photons.

Also, read

• NCERT Solutions for Class 11 Physics
• NCERT Solutions for Class 12 Physics
• NCERT Solutions for All Subjects

Types of Light Source

we have a lot of sources of light, but all of them can be categorised under two categories.

• Natural Light Sources

In simple words, natural light is the light that is generated by a natural source. The universe is filled with numerous sources of light. The emitted light from a few sources of light reaches the Earth. The following natural light sources emit light: The Sun is one of the major sources of light of the earth. Also, the Sun is the main light source for the entire Solar System. In the sun, heat and light are produced by a process called Nuclear Fusion.

Many other stars also produce light, but only a small amount or no amount from them reaches the earth because of the large distance. The moon does not have its own light. So, it reflects the light from the Sun and acts as one of the natural light sources on the Earth.

Bioluminescence - Some living organisms produce light by a chemical reaction that occurs within them.[Another natural light source]
For Example- Fireflies, jellyfish, glowworms, some microorganisms and deep-sea plants.

Volcanic eruptions & Lightning also emit light.

Examples of natural sources of light or name two natural sources of light- Sun, Stars, etc.

• Artificial Light Sources or Man-Made Sources of Light

Apart from natural light sources, there are different artificial light sources that emit light. The different artificial light sources can be put the following categories

Incandescent Sources

When certain objects are heated to a high temperature, they begin to emit both infrared and visible light in the process.

Example- Candles, and incandescent lamps.

Luminescent Sources

By bypassing current (i.e., by accelerating charges in a luminescent material.) Through the material, light can be produced.

Example- Fluorescent tube light, electric bulb

Gas Discharge Sources

Light can be produced/created by passing electricity across a certain gas at very low pressure.

Example – Neon lamp, Sodium lamp.

Torch, Candle, Bulb, Lamp, etc. are examples of artificial sources of light.