Environmental Protection Agency (EPA) MVAC Certification

What type of light does the ozone layer absorb and scatter from the sun?

1. Infrared light

2. Visible light

3. Ultraviolet light

4. X-ray light

The correct answer is: Ultraviolet light

The ozone layer plays a crucial role in protecting life on Earth by absorbing and scattering ultraviolet (UV) light from the sun. This is significant because UV light can be harmful to living organisms, leading to health issues such as skin cancer and cataracts, as well as negatively impacting ecosystems. The ozone layer is primarily composed of ozone (O3) molecules, which absorb a large portion of the sun's harmful UV radiation, particularly the UV-B and UV-C wavelengths. By filtering out this radiation, the ozone layer helps to maintain the balance of the Earth's environment and ensures that life can thrive. In contrast, while infrared light, visible light, and X-ray light interact with the atmosphere in different ways, they are not absorbed to the same extent by the ozone layer as ultraviolet light. For instance, infrared light is mostly transmitted through the atmosphere, and visible light is essential for photosynthesis but is not the focus of the ozone layer's protective function. X-rays are also absorbed by the atmosphere but are not significantly dealt with by the ozone layer specifically. Thus, the accurate answer highlights the ozone layer's vital protective role against ultraviolet light, making it essential for both human health and environmental integrity.