Which of the following best describes a key difference between the light emitted by a typical grow bulb and sunlight in terms of wavelength and frequency?

• A. Sunlight emits only infrared wavelengths, while grow bulbs emit only visible light.
• B. Grow bulbs and sunlight both emit identical spectra with no difference in wavelength or frequency distribution.
• C. Grow bulbs emit light with higher frequencies than sunlight, resulting in more ultraviolet radiation.
• D. Grow bulbs emit light with a narrower range of wavelengths, often concentrated in the red and blue regions, while sunlight contains a broad spectrum of wavelengths across the visible range.

Answer: (D)

Verified step by step guidance

1. Understand that light can be characterized by its wavelength (\( \lambda \)) and frequency (\( \nu \)), which are related by the equation \(\nu = \frac{c}{\lambda}\), where \(c\) is the speed of light.
2. Recognize that sunlight is a natural light source that emits a broad spectrum of electromagnetic radiation, including a wide range of visible wavelengths, as well as ultraviolet and infrared radiation.
3. Know that typical grow bulbs are designed to emit light primarily in specific wavelength ranges, usually concentrated in the red and blue regions of the visible spectrum, to optimize plant growth.
4. Compare the emission spectra: sunlight has a continuous and broad distribution of wavelengths and frequencies, while grow bulbs have a narrower emission spectrum focused on certain wavelengths.
5. Conclude that the key difference is that grow bulbs emit light with a narrower range of wavelengths (and thus frequencies), often targeting red and blue light, whereas sunlight provides a broad spectrum across the visible range and beyond.