Which of the following blocks will release heat fast?
Correct answer: C. Rough black surface
- A. Rough white surface
- B. Polished white surface
- C. Rough black surface
- D. Polished black surface
Explanation
The key factor in determining how fast a surface releases heat is its ability to absorb light. Surfaces that absorb more light will heat up faster and consequently release heat faster.Black surfaces absorb more light compared to white surfaces because they absorb a broader spectrum of light. Therefore, a black surface, whether rough or polished, will generally release heat faster than a white surface.Roughness can enhance absorption to some extent by increasing the surface area for light to interact with. However, the color of the surface remains a dominant factor in determining its ability to absorb light.Polishing a surface generally increases its reflectivity, regardless of its color. So, polished surfaces, whether white or black, will absorb less light compared to their rough counterparts, leading to slower heat release.
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About Dawn of Modern Physics
Classical physics cannot explain blackbody radiation and related observations, leading to Planck’s quantum theory, in which energy is emitted or absorbed in discrete packets. Photons provide the particle model of light, with energy and momentum linked to frequency and wavelength, including the photoelectric effect and its threshold frequency.
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