Practice portal › GUJCET › Ray Optics and Optical Instruments

Optical Instruments for GUJCET: 12 solved questions

Real GUJCET paper questions on optical instruments, part of ray optics and optical instruments. Each opens with the options, the correct answer and a step-by-step solution. Papers run from 2009 to 2026. No sign-in needed to read them.

What this topic asks

• Telescopes — 7 questions
• Microscopes — 5 questions

All 12 questions with solutions

• An astronomical telescope has objective and eye-piece lenses of powers 0.5 D and 20 D respectively. What will… GUJCET 2009
• For an astronomical telescope, the focal length of the objective lens is f₀ and that of the eye-piece lens is… GUJCET 2017
• A convex lens of focal length 12.5 cm is used as a simple microscope. When the image is formed at infinity, t… GUJCET 2017
• If the tube length of an astronomical telescope is 96 cm and its magnifying power is 15 for normal setting, t… GUJCET 2019
• Consider a refracting telescope whose objective has a focal length of 1 m and the eyepiece a focal length of… GUJCET 2024
• If the tube-length (L) of a compound microscope increases, then its magnification . GUJCET 2025
• If in compound microscope objective with focal length 1.0 cm, eyepiece with focal length 2.0 cm, tube length… GUJCET 2026
• If the tube length of an astronomical telescope is 105 cm and its magnifying power is 20 for normal setting,… GSEB Board March 2018
• For a compound microscope f₀=1 cm, fₑ=2 cm and the tube length L=20 cm. Then the total magnification is . GSEB Board August 2020
• The focal lengths of the objective lens and the eyepiece of a telescope are fₒ and fₑ respectively. The magni… GSEB Board March 2022
• The focal length of the objective is 100 cm and the focal length of an eyepiece is 1 cm, then the tube length… GSEB Board July 2022
• A convex lens of focal length 10 cm is used as a simple microscope. When the image of an object is obtained a… RS Academy GUJCET booklet