In monochromatic red light a blue book will probably appear to be_________________?
Correct answer: A. black
- A. black
- B. purple
- C. green
- D. no scientific reasoning available
Explanation
A blue book reflects mainly blue wavelengths, but red illumination provides almost no blue light to reflect, so the book appears black or very dark. Students may choose purple by mixing the colour names, but purple appearance would require suitable red and blue light reaching the eye.
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About Optics
Light is studied through reflection, refraction, dispersion, interference, diffraction and polarization, linking ray behavior with its wave nature. Questions may involve mirrors, lenses, optical instruments, refractive index and image formation, while geometrical optics deals with rays and wave optics explains effects such as interference and diffraction.
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