The periodic time of rotation of a certain star is 22 days and its radius is 7 x 10^8 metres. If the wavelength of light emitted by its surface is 4320 Å, the Doppler shift will be: (1 day = 86400 sec)
Correct answer: A. 0.033 Å
- A. 0.033 Å
- B. 0.33 Å
- C. 3.3 Å
- D. 33 Å
Explanation
To calculate the Doppler shift, you can use the formula: Δλ/λ = v/c, where Δλ is the change in wavelength, λ is the original wavelength, v is the speed of the star's surface, and c is the speed of light. By substituting the values provided in the question and solving the equation, you will arrive at a Doppler shift of 0.033 Å. This value represents the change in wavelength due to the motion of the star. The other options provide incorrect values, which may result from errors in calculation or misapplication of the formula.
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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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