The resolving power of a telescope is increased by
Correct answer: B. increasing the diameter of its objective lens or mirror
- A. increasing the magnification only
- B. increasing the diameter of its objective lens or mirror
- C. using a longer eyepiece
- D. using light of longer wavelength
Explanation
Resolution is limited by diffraction at the aperture, so a larger objective produces a smaller diffraction disc and separates closer objects, which is the main reason research telescopes are built so large. Magnification without resolution simply enlarges a blur. A shorter wavelength also improves resolution, which is why ultraviolet and electron imaging outperform visible light.
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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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