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BITSAT2023PhysicsRay OpticsActual

In a reflecting telescope, a secondary mirror is used to:

Options

  1. Areduce the problem of mechanical support
  2. Bremove spherical aberration
  3. Cmake chromatic aberration zero
  4. Dmove the eyepiece outside the telescopic tube

Correct answer

D. move the eyepiece outside the telescopic tube

Step-by-step solution

(d) To redirect the light that enters the telescope to the eyepiece or camera. The primary mirror of a reflecting telescopes gathers the light and reflects towards the secondary mirror which then reflect the light towards the eyepiece allowing the observer to see image. It has advantage of a large focal length in a short telescope.

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