Sample questions
You've seen the pattern — here are a few of the actual PYQs.
CDS2025
Which one among the following is used in a simple microscope ?
- A Diverging lens
- B Concave mirror
- C Converging lens ✓
- D Plane mirror
✓ Correct answer: (C)
Science & Technology › Physics & Chemistry
CDS2018
When a convex lens produces a real image of an object, the minimum distance between the object and image is equal to
- A the focal length of the convex lens
- B twice the focal length of the convex lens
- C four times the focal length of the convex lens ✓
- D one half of the focal length of the convex lens
✓ Correct answer: (C)
Science & Technology › Physics & Chemistry
CDS2014
The upper and lower portions in common type of bi-focal lenses are respectively
- A concave and convex ✓
- B convex and concave
- C both concave of different focal lengths
- D both convex of different focal lengths
✓ Correct answer: (A)
Science & Technology › Physics & Chemistry
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