CDS (II) 2017 · General Knowledge
A full General Knowledge paper in the UPSC CDS pattern: 120 questions in 2 hours, with a third of the question's marks deducted for every wrong answer. Physics, Chemistry, Biology, defence and security, History, Geography, Polity, Economy and current events.
120questions
100marks
2 hoursno calculator
41/66/13easy / medium / hard
Topics in this paper
General Knowledge · 120 questions
- Modern India5
- World geography5
- Medieval India4
- Units3
- Optics3
- Olympics3
- Sports3
- Freedom struggle3
- Indian geography3
- Parliament3
- Instruments2
- Human digestion2
- Atomic structure2
- Organic chemistry2
Sample question from this paper
Optics · medium
An object is placed between the pole and the focus of a concave mirror. The image formed is
- A. real, inverted and enlarged
- B. real, inverted and diminished
- C. virtual, erect and diminished
- D. virtual, erect and enlarged
Show answer and solution
Answer: D
When the object lies within the focal length, the reflected rays diverge and appear to come from behind the mirror, giving a virtual and erect image that is larger than the object. This is how a shaving mirror works. Real images are always inverted and form only when the object is beyond the focus.
When the object lies within the focal length, the reflected rays diverge and appear to come from behind the mirror, giving a virtual and erect image that is larger than the object. This is how a shaving mirror works. Real images are always inverted and form only when the object is beyond the focus.