Ray Optics and Optical Instruments — Class 12 CBSE Physics revision notes
A 3-page visual revision sheet for Ray Optics and Optical Instruments, written for Class 12 CBSE Physics. Formulas, diagrams and the traps that cost marks, laid out to be read the night before rather than the term before. Free, and it opens inside CapCompass.
What this Ray Optics and Optical Instruments sheet covers
- Object distance
- Mirror formula
- Image distance
- Concave vs convex mirror
- Concave mirror
- Convex mirror
- New Cartesian sign convention
- Mirror formula and magnification
- focal length from radius of curvature
- linear magnification
- Refraction and total internal reflection
- Snell's law
- absolute refractive index
- critical angle, denser medium of index n
- Where TIR shows up
- Lenses
- thin lens formula
- lensmaker's formula
- magnification
- power of a lens, f in metres
- lenses in contact
- Prism and dispersion
- angle of the prism
- deviation
- at minimum deviation, i = e, r_1 = r_2 = A/2
- Optical instruments
- simple microscope, image at the near point
- compound microscope, normal adjustment
- astronomical telescope, normal adjustment
- Symbols
- Traps that cost marks
- Tricks that save time
How CapCompass uses this sheet
These notes are not a standalone PDF. CapCompass plans Physics chapter by chapter against your real exam dates and free hours, and when the plan reaches Ray Optics and Optical Instruments the sheet opens inside the study block itself — at the page covering the sub-topic that block is on, with the timer still running. Revision arrives at the moment the plan says revise, instead of having to be gone looking for.