MDCAT Physics — Optics
Optics is a core Physics topic in the PMDC MDCAT syllabus, covering 11 subtopics. Below are the subtopics to revise, how often the topic appears in past papers, and real past-paper MCQs to try.
Subtopics (11)
- Brewster
- Diffraction
- Diffraction Grating
- Human Eye (Near Point, Far Point)
- Interference
- Lenses and Optical Instruments
- Magnification and Image Formation
- Nature of Light
- Optical Fibers and Total Internal Reflection
- Polarization
- Young's Experiment
How Optics is tested
Across the 16 MDCAT past papers on ParhaiKrlo, Optics accounts for 7 questions. It appears in 4 of them, about 1.8 questions a paper. The heaviest was MDCAT 2008, with 4 questions, and the most recent is MDCAT 2011, with 1.
| Paper | Questions |
|---|---|
| MDCAT 2011 | 1 |
| MDCAT 2010 | 1 |
| MDCAT 2009 | 1 |
| MDCAT 2008 | 4 |
Optics MCQs from the MDCAT past papers
Try each one before opening the answer. Each comes with a short explanation.
- Q1 · MDCAT 2011 · Optics
The normal human eye can focus a sharp image of an object on the eye if the object is located at certain distance called
- A.Least Point
- B.Near Point
- C.Far Point
- D.Distinct Point
Show answer
Answer: B. Near Point — The near point is the closest distance at which the normal eye can focus a sharp image comfortably (about 25 cm for a typical adult).
- Q2 · MDCAT 2010 · Optics
Which one of the following lights travels fastest in optical fibers?
- A.Visible light
- B.Ultraviolet light
- C.Ordinary light
- D.Invisible infrared light
Show answer
Answer: D. Invisible infrared light — In glass the refractive index is smallest for the longest wavelengths, so infrared travels fastest (v = c/n) — and it also suffers the least loss, which is why fibres use it.
- Q3 · MDCAT 2009 · Optics
The information received at the other end of a fibre can be inaccurate due to _______ of the light signal.
- A.Longer wavelengths
- B.Frequency
- C.Intensity
- D.Dispersion or Spreading
Show answer
Answer: D. Dispersion or Spreading — Dispersion (spreading) of the light pulse along the fibre smears out the signal, making received information inaccurate.