Beyond infrared with less frequency and longer wavelength is what?

Beyond infrared with less frequency and longer wavelength is what?

• A. Ultraviolet radiation
• B. Infrared
• C. Microwave
• D. X-rays

Answer: (C)

The key thing to keep in mind is that as you move to longer wavelengths, the frequency drops because the speed of light is constant. Infrared sits toward the longer-wavelength side of the spectrum, and “beyond infrared” means even longer wavelengths and lower frequencies. Microwave fits that description: its wavelengths are longer than infrared, and its frequency is lower. Ultraviolet and X-rays have shorter wavelengths and higher frequencies, so they don’t match. Radio waves would be even longer, but they aren’t the one described here. So the radiation described is microwave.

The key thing to keep in mind is that as you move to longer wavelengths, the frequency drops because the speed of light is constant. Infrared sits toward the longer-wavelength side of the spectrum, and “beyond infrared” means even longer wavelengths and lower frequencies. Microwave fits that description: its wavelengths are longer than infrared, and its frequency is lower. Ultraviolet and X-rays have shorter wavelengths and higher frequencies, so they don’t match. Radio waves would be even longer, but they aren’t the one described here. So the radiation described is microwave.