Question

Which has the shorter wavelength: blue light or violet light?

Short answer

Violet light has a shorter wavelength than blue light.

Step-by-step solution

Understanding the Electromagnetic Spectrum

The electromagnetic spectrum is the range of all types of EM radiation. Visible light, which is a part of this spectrum, ranges from red to violet. The order, from longest to shortest wavelength, goes from red light (which has the longest wavelength) to violet light (which has the shortest wavelength in the visible spectrum).

Identifying the Colors

In the visible spectrum, blue light and violet light are next to each other, with blue light between green and violet. Violet light comes after blue light, right before moving into ultraviolet light, which is not visible.

Comparing Wavelengths

Since the colors of light are arranged from longest to shortest wavelength in the visible spectrum, violet light has a shorter wavelength compared to blue light. Wavelength decreases as you move from green to violet in the spectrum.

Concluding the Comparison

Based on the known order of decreasing wavelength in the visible light spectrum, we can determine that violet light has a shorter wavelength than blue light.

Key concepts

Wavelength

Wavelength is a fundamental concept in understanding light and the electromagnetic spectrum. It represents the distance between two consecutive peaks or troughs of a wave. Wavelength is usually measured in meters and is represented by the Greek letter lambda (\(\lambda\)).
Understanding wavelength is key to distinguishing different forms of light and electromagnetic radiation.

• Shorter wavelengths mean higher energy and frequency.
• Longer wavelengths correspond to lower energy and frequency.

In the context of visible light, the wavelength directly affects the color we perceive. For instance, red light has longer wavelengths than blue or violet light, which translates to lower energy for red compared to the high energy of violet. Essentially, wavelength helps us categorize and understand the different types of light we encounter in everyday life.

Visible Light

Visible light is a small portion of the electromagnetic spectrum that is detectable by the human eye. It ranges from about 380 nanometers (nm) to 750 nm, covering all colors from violet to red.
Within this range, each color has its specific wavelength and energy level.

• Red has the longest wavelength, making it the lowest energy visible light.
• Violet has the shortest wavelength, which means it carries more energy.

Visible light is crucial for life on Earth as it is the primary source of energy for photosynthesis and affects the way we see the world. It also plays an important role in modern technology, from photography to LED lighting. Understanding visible light and its properties enriches our perception of the world by allowing us to identify different colors and their wavelengths.

Color Spectrum

The color spectrum refers to the distribution of colors that are produced when light is spread out according to its wavelength. When white light passes through a prism, it separates into its constituent colors, ranging from red, with the longest wavelength, to violet, with the shortest.
This separation occurs because different wavelengths are refracted or bent by different amounts.
The color spectrum is essential in many fields, including art, where artists mix pigments to create various hues, and in science, where the spectrum helps identify chemical compositions through spectral lines.

• Red to violet: This order corresponds to increasing energy level.
• Beyond visible light: Infrared and ultraviolet are also part of the spectrum but are not visible to the human eye.

By understanding the color spectrum, we can appreciate the complexity and beauty of light. It shows us how simple white light is composed of a rich variety of colors, each with distinct properties tied to its wavelength.