What Is Light: The Basics of Color, Speed, and Vision

Light surrounds us every moment of the day, yet we rarely stop to think about what it really is. From the colors we see to the speed at which it travels, light is one of the most fascinating phenomena in Hashem’s world.

What Is Light

Light is a form of electromagnetic radiation that exists within a specific range, between infrared and ultraviolet rays. These two types of radiation are outside the range visible to the human eye. What we call light is simply the part of this spectrum that we are able to see.

Light is made up of waves of different lengths, and each wavelength corresponds to a different color. When light hits an object, some of these waves are absorbed by the surface, while others are reflected back. The reflected waves are what reach our eyes, and that is how we perceive color.

Why Black and White Are Different

You may have noticed that the primary colors are red, blue, and yellow, but not black and white. That is because black and white are not considered colors in the same way.

Black is the absence of light. When light hits a black surface, it is absorbed completely, and no light is reflected back to our eyes.

White is the opposite. It is a combination of all colors. When light hits a white surface, it is fully reflected, which is why we see it as white.

The light we see is actually made up of seven colors, known as the colors of the rainbow. When light passes through a prism, it separates into these different wavelengths, allowing us to see each color clearly. The same thing happens in nature when sunlight passes through tiny droplets of water in the air, creating a rainbow.

The Speed of Light

Light travels at an incredible speed. In a vacuum, it moves at about 300,000 kilometers per second.

To understand this, imagine standing on the moon and looking back at Earth. The light from Earth would reach you in just over one second.

Because light moves so quickly, it is also used to measure enormous distances in space. A light year is the distance that light travels in one year, helping us understand the vast scale of the universe.

Light travels much faster than sound. Sound moves at about 344 meters per second. This is why, during a thunderstorm, we see lightning before we hear thunder. Although they happen at the same time, the light reaches us almost instantly, while the sound takes longer to arrive.

A Glimpse Into a Deeper World

What seems simple at first glance is actually full of depth and wonder. Light not only allows us to see the world, but also reveals the intricate order and beauty within it.

Taking a moment to understand it can deepen our appreciation for the world around us.