As you move from red to violet across the visible spectrum (the colors of the rainbow), how do the wavelength and frequency of light change?

• A. Both wavelength and frequency increase.
• B. Wavelength increases and frequency decreases.
• C. Both wavelength and frequency decrease.
• D. Wavelength decreases and frequency increases.

Answer: (D)

Verified step by step guidance

1. Recall that the visible spectrum ranges from red light to violet light, with red having the longest wavelength and violet having the shortest wavelength.
2. Understand the relationship between wavelength (\( \lambda \)) and frequency (\( \nu \)) of light, which is given by the equation: \[ c = \lambda \times \nu \] where \( c \) is the speed of light, a constant.
3. Since the speed of light \( c \) is constant, if the wavelength \( \lambda \) decreases as you move from red to violet, the frequency \( \nu \) must increase to keep the product \( \lambda \times \nu \) equal to \( c \).
4. Therefore, as you move from red to violet across the visible spectrum, the wavelength decreases and the frequency increases.
5. This explains why the correct answer is: Wavelength decreases and frequency increases.