Platinum wire becomes yellow at a temperature of _ degree C.
Correct answer: C. 1300
- A. 900
- B. 500
- C. 1300
- D. 1600
Explanation
Correct option is C. On heating the black platinum wire, temperature increases and thus the peak wavelength decreases because of which the color of the wire changes from red (λ=700 nm) to yellow at 1300°C.
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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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