Question

What is the wavelength range for visible light? Does ultraviolet light have shorter or longer wavelengths than visible light?

Short answer

Visible light ranges from about 380 nm to 750 nm. Ultraviolet light has shorter wavelengths than visible light, ranging from 10 nm to 400 nm.

Step-by-step solution

Understanding Visible Light

Visible light is the portion of the electromagnetic spectrum that can be seen by the human eye. This range is typically from approximately 380 nm (nanometers) to approximately 750 nm. The violet end of the spectrum has shorter wavelengths, while the red end has longer wavelengths.

Ultraviolet Light Wavelength

Ultraviolet (UV) light is part of the electromagnetic spectrum that falls between visible light and X-rays. It has wavelengths shorter than those of visible light, typically ranging from about 10 nm to 400 nm.

Comparing Wavelengths

When comparing ultraviolet light with visible light, we see that ultraviolet light has a shorter wavelength range (10 nm to 400 nm) compared to visible light (380 nm to 750 nm). This means ultraviolet light's wavelengths are shorter than all the wavelengths within the visible light range.

Key concepts

Visible Light

Visible light is the part of the electromagnetic spectrum that is detectable by the human eye. It plays a crucial role in various aspects of daily life, providing the light by which we see and interact with the world. This light comes from many natural and artificial sources, such as the sun and light bulbs.
The range of wavelengths for visible light typically spans from about 380 nanometers (nm) to 750 nm. Within this range:

• Violet light has the shortest wavelengths near 380 nm.
• Red light has the longest wavelengths around 750 nm.

Therefore, when we see different colors, we are perceiving light at different wavelengths within this visible spectrum. Understanding this concept helps in various fields, including art, physics, and even biology.

Ultraviolet Light

Ultraviolet (UV) light lies just beyond the visible light spectrum. Although humans can't see UV light, it is significant for scientific study because of its effects and applications.
UV light's wavelength range is from approximately 10 nm to 400 nm, which is shorter than that of visible light. This measurement puts UV light between the electromagnetic spectrum's visible light section and the X-ray section.
There are several types of ultraviolet light, categorized by their wavelengths:

• UVA (400-315 nm) – Often associated with tanning and aging, it has the longest UV wavelengths.
• UVB (315-280 nm) – Known for causing sunburn and contributing to skin cancer.
• UVC (280-100 nm) – Mostly absorbed by the Earth's atmosphere and not typically a concern for ground-level UV exposure.

Understanding these distinctions is essential for recognizing UV light's impact on health and technology.

Wavelengths

Wavelengths are a key concept in understanding the electromagnetic spectrum. They indicate the distance between successive peaks of a wave and are typically measured in nanometers (nm) for light frequency.
In the spectrum, different regions have different wavelength ranges that define their specific characteristics and behaviors. Here are some general insights:

• Shorter wavelengths typically have higher energy and frequency. For instance, ultraviolet light has shorter wavelengths and thus more energy than visible light.
• Longer wavelengths, like those of red light, have less energy compared to violet light.

To fully appreciate how different parts of the spectrum interact with matter, understanding wavelength is crucial. It not only determines light properties but also influences how light is absorbed, reflected, and transmitted by various materials.