alleryIn vacuum, c=3×10^8 m/s and f=2×10^14 Hz. Wavelength and band?
A1.5 μm; visible light
B1.5 mm; microwaves
C1.5 μm; infrared
D1.5 nm; X-rays
Answer & Solution
Correct answer: C. 1.5 μm; infrared
The wavelength is c/f = 1.5 μm, which lies in the infrared band.
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