Question

Name the radiations of wavelength just longer than $8\times {10}^{-7}m$.

• A. infrared
• B. ultrared
• C. infraviolet
• D. ultraviolet

Answer 1

The correct option is A infrared

In the order of increasing wavelength, the waves are Gamma rays ($<1nm$), X-rays ($1-10nm$), infrared rays ($700-{10}^{5}nm$), micro waves (${10}^5-{10}^{8}nm$), radio waves (${>10}^{8}nm$).
Hence, the radiations of wavelength just longer than ${8\times 10}^{-7}m$ is Infrared.