Electromagnetic spectrum classification by wavelength

Steps:

• Recall standard wavelength ranges: gamma rays (<0.01 nm), X-rays (0.01-10 nm), infrared (700 nm-1 mm), microwaves (1 mm-1 m), radio waves (>1 m).
• Assume table lists five wavelengths in increasing order, from shortest (gamma) to longest (radio).
• Match each wavelength to its principal radiation band based on these ranges.
• Select the option that correctly sequences the bands from shortest to longest wavelength.

Why A is correct:

• Option A matches the standard spectrum order for increasing wavelengths, aligning with the inverse relationship between wavelength and frequency per c = fλ.

Why the others are wrong:

• B reverses order and misplaces ultraviolet before infrared.
• C reverses order and omits ultraviolet while including X-ray before gamma.
• D jumbles bands, placing infrared before ultraviolet and microwave after.

Final answer: A