JEE Main · Physics · Ray Optics and Optical Instruments
Refraction and Snell's Law: JEE Main previous year questions
40 questions in the 108 JEE Main shifts Lumi analysed, in 7 of 8 years. Pattern: Asked most years. 10 came in 2024–26. Here is how it is asked and which ideas come back.
- Questions
- 40
- in 36 of 108 shifts
- Years asked
- 7/8
- last asked 2026
- Weighted estimate
- 0.3
- model; history: 0.3 a shift on average, typically 0.1–0.6
Key findings
- 01
Asked in 7 of 8 years with analysed shifts and in 36 of 108 shifts: 40 questions, #83 of 196 topics.
- 02
50% of its questions since 2020 tested an idea no earlier year had asked; 13 repeated an idea from the year before.
- 03
The most repeated idea is Total Internal Reflection, asked 9 times in 9 shifts (2020, 2021, 2022, 2023, 2024, 2025), most often as “maximum incidence angle for total internal reflection”.
- 04
JEE Main has asked 18 of the 59 ideas in this topic; 41 have never been asked, directly or inside another question.
- 05
Mostly asked as single correct (53%); 33% need a numerical answer, 30% are easy and 18% hard.
- 06
The skill tested most is multi-step (40%), then calculation (33%).
Questions a shift, year by year
Out of the 25 Physics questions in a shift. Years differ in how many shifts Lumi analysed, so each year is scaled to one shift.
Raw count: 2017: 0 in 1 shift · 2020: 5 in 12 shifts · 2021: 5 in 24 shifts · 2022: 12 in 24 shifts · 2023: 8 in 12 shifts · 2024: 4 in 18 shifts · 2025: 5 in 8 shifts · 2026: 1 in 9 shifts.
- Up to 2023
- 0.3
- a shift, of 25
- Since 2024
- 0.3
- 0.0
- Usual gap
- 1.0 yrs
- between years asking it
- Shifts with it
- 36/108
- 33% of analysed shifts
Revise first
- Total Internal Reflection · asked 2020, 2021, 2022, 2023, 2024, 2025
- Refractive Index and Speed · asked 2022, 2025
- Apparent Depth of Immiscible Liquids · asked 2020, 2023, 2024, 2025
How it is asked
Difficulty, format and skill
Across all 40 questions on Refraction and Snell's Law since 2017.
Difficulty
QUESTIONS- Easy12 · 30%
- Medium21 · 53%
- Hard7 · 18%
Format
SHARE- Single correct · 21 Q53%
- Numerical value · 13 Q33%
- Diagram based · 4 Q10%
- Assertion–reason · 2 Q5%
Skill tested
SHARE- Multi-step · 16 Q40%
- Calculation · 13 Q33%
- Application · 6 Q15%
- Conceptual · 4 Q10%
- Diagram reading · 1 Q3%
Repeats
New idea, or one asked before?
Each column is a year. Blue questions tested an idea no earlier year had asked; navy ones went back to an idea from an earlier year. 2017 is the first year, so everything in it counts as new. Heights are question counts, and Lumi analysed 1 to 24 shifts a year, so compare the split inside a column rather than heights across years.
- Idea asked for the first time
- Idea asked in an earlier year
Coverage of the topic
JEE Main has asked 18 of the 59 ideas in this topic. 41 have never been asked yet.
- Asked directly18 · 31%
- Touched inside another question0 · 0%
- Never asked41 · 69%
Ideas come from Lumi’s JEE syllabus map. A never-asked idea is not a safe skip: across all of JEE Main, 22% of questions since 2024 tested an idea no earlier year had asked.
Drill down
Chapter, idea, question
Every idea JEE Main tested in this topic, with its eight years. Open one to read the questions.
16 ideas inside
Squares are the 8 years with analysed shifts, 2017 to 2026. A number is the questions that year when there is more than one; the shade is scaled to one shift, so a year with more analysed shifts (1 to 24 a year) does not look darker. Share is of the level above.
Ideas
Every idea inside this topic
18 different ideas were tested; 8 came more than once.
maximum incidence angle for total internal reflection
Single correct · 9 shiftsrefraction from direction vectors
Numerical value · 4 shifts · 2 numericalheight of liquid from apparent shift
Numerical value · 4 shifts · 2 numericalrefractive index by travelling microscope with vernier
Numerical value · 4 shifts · 2 numericalassertion-reason on refractive index and optical density
Assertion–reason · 3 shifts · 1 numericalwavelength in medium from frequency
Single correct · 2 shiftslateral shift in slab at critical angle incidence
Numerical value · 2 shifts · 2 numericalcritical angle from speeds in two media
Single correct · 2 shiftsactual velocity from apparent velocity in refraction
Numerical value · 1 shift · 1 numericalassertion-reason on phase difference in media
Assertion–reason · 1 shiftwavelength and frequency after refraction
Single correct · 1 shiftarea of surface through which light emerges
Numerical value · 1 shift · 1 numericalrefractive index from deviation at interface
Single correct · 1 shiftthickness from travel time difference
Single correct · 1 shiftangle difference from refraction of ray given as vector
Numerical value · 1 shift · 1 numericalray through parallel media with parallel emergent ray
Diagram based · 1 shiftcolours emerging from right-angled prism
Diagram based · 1 shiftangle between reflected and refracted rays
Numerical value · 1 shift · 1 numerical
| Idea | Years asked | Times | Shifts | Format | Numerical |
|---|---|---|---|---|---|
| Total Internal Reflectionmaximum incidence angle for total internal reflection | 9 | 9 | Single correctMulti-step | – | |
| Snell's Law Applicationrefraction from direction vectors | 4 | 4 | Numerical valueMulti-step | 2 | |
| Apparent Depth of Immiscible Liquidsheight of liquid from apparent shift | 4 | 4 | Numerical valueCalculation | 2 | |
| Apparent Depth and Shiftrefractive index by travelling microscope with vernier | 4 | 4 | Numerical valueMulti-step | 2 | |
| Refractive Index and Speedassertion-reason on refractive index and optical density | 3 | 3 | Assertion–reasonCalculation | 1 | |
| Invariance of Frequency in Refractionwavelength in medium from frequency | 2 | 2 | Single correctCalculation | – | |
| Lateral Shift in Slabslateral shift in slab at critical angle incidence | 2 | 2 | Numerical valueCalculation | 2 | |
| Critical Angle Between Two Dense Mediacritical angle from speeds in two media | 2 | 2 | Single correctApplication | – | |
| Apparent Distance in Two Media (Bird-Fish Problem)actual velocity from apparent velocity in refraction | 1 | 1 | Numerical valueMulti-step | 1 | |
| Optical Path Length Calculationassertion-reason on phase difference in media | 1 | 1 | Assertion–reasonConceptual | – | |
| Relative Refractive Index and Wave Parameterswavelength and frequency after refraction | 1 | 1 | Single correctApplication | – | |
| Circle of Illuminance (Fish-Eye View)area of surface through which light emerges | 1 | 1 | Numerical valueMulti-step | 1 | |
| Deviation at a Single Interfacerefractive index from deviation at interface | 1 | 1 | Single correctCalculation | – | |
| Time of Flight in a Mediumthickness from travel time difference | 1 | 1 | Single correctMulti-step | – | |
| Vector Form of Snell's Lawangle difference from refraction of ray given as vector | 1 | 1 | Numerical valueMulti-step | 1 | |
| Normal Shift across Multiple Slabsray through parallel media with parallel emergent ray | 1 | 1 | Diagram basedConceptual | – | |
| Wavelength Dependence of TIRcolours emerging from right-angled prism | 1 | 1 | Diagram basedDiagram reading | – | |
| Partial Reflection and Refractionangle between reflected and refracted rays | 1 | 1 | Numerical valueCalculation | 1 |
Times and shifts count every analysed shift. Across JEE Main, 78% of questions since 2024 went back to an idea an earlier year had asked; the rest were new. All repeated ideas
Every question
Refraction and Snell's Law questions, year by year
The opening words of each question as it appeared in the official paper, with the idea it tested. Open one for its options and the official answer.
JEE Main 20261 question in 1 shift
- 8 Apr, Shift 2Q42Light ray incident along a vector emerges out along vector…
Idea: Snell's Law Application
MediumDiagram based · figure
JEE Main 20255 questions in 4 shifts
- 3 Apr, Shift 2Q42A monochromatic light of frequency Hz travelling through air, is incident on a medium of refractive index '2'.…
Idea: Invariance of Frequency in Refraction
EasySingle correct - 4 Apr, Shift 2Q47If an optical medium possesses a relative permeability of and relative permittivity of , then the…
Idea: Refractive Index and Speed
MediumNumerical value - 7 Apr, Shift 1Q50A container contains a liquid with refractive index of 1.2 up to a height of 60 cm and another liquid having refractive index 1.6 is added…
Idea: Apparent Depth of Immiscible Liquids
Asked the year beforeMediumNumerical value - 7 Apr, Shift 2Q41Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : Refractive…
Idea: Refractive Index and Speed
EasyAssertion–reason - 7 Apr, Shift 2Q42A transparent block A having refractive index is surrounded by another medium of refractive index as shown in figure.…
Idea: Total Internal Reflection
Asked the year beforeMediumSingle correct · figure
JEE Main 20244 questions in 4 shifts
- 4 Apr, Shift 2Q52A light ray is incident on a glass slab of thickness cm and refractive index . The angle of incidence is equal to…
Idea: Lateral Shift in Slabs
MediumNumerical value - 6 Apr, Shift 2Q50In finding out refractive index of glass slab the following observations were made through travelling microscope 50 vernier scale division…
Idea: Apparent Depth and Shift
Asked the year beforeHardSingle correct - 8 Apr, Shift 1Q43Critical angle of incidence for a pair of optical media is . The refractive indices of first and second media are in the ratio:
Idea: Total Internal Reflection
Asked the year beforeEasySingle correct - 27 Jan, Shift 1Q59Two immiscible liquids of refractive indices and respectively are put in a beaker as shown in the figure. The…
Idea: Apparent Depth of Immiscible Liquids
Asked the year beforeEasyNumerical value · figure
JEE Main 20238 questions in 6 shifts
- 6 Apr, Shift 1Q36A monochromatic light wave with wavelength and frequency in air enters another medium. If the angle of incidence and…
Idea: Relative Refractive Index and Wave Parameters
New ideaEasySingle correct - 6 Apr, Shift 1Q52A pole is vertically submerged in swimming pool, such that it gives a length of shadow 2.15 m within water when sunlight is incident at an…
Idea: Snell's Law Application
Asked the year beforeHardNumerical value - 6 Apr, Shift 2Q45Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R Assertion A: The phase difference of…
Idea: Optical Path Length Calculation
New ideaEasyAssertion–reason - 11 Apr, Shift 1Q35The critical angle for a denser-rarer interface is . The speed of light in rarer medium is m/s. The speed of…
Idea: Total Internal Reflection
Asked the year beforeEasySingle correct - 11 Apr, Shift 2Q56As shown in the figure, a plane mirror is fixed at a height of from the bottom of tank containing water…
Idea: Apparent Depth and Shift
Asked the year beforeHardNumerical value · figure - 12 Apr, Shift 1Q46An ice cube has a bubble inside. When viewed from one side the apparent distance of the bubble is 12 cm. When viewed from the opposite…
Idea: Apparent Depth and Shift
Asked the year beforeMediumSingle correct - 13 Apr, Shift 1Q44A vessel of depth 'd' is half filled with oil of refractive index and the other half is filled with water of refractive index .…
Idea: Apparent Depth of Immiscible Liquids
EasySingle correct - 13 Apr, Shift 1Q52A fish rising vertically upward with a uniform velocity of , observes that a bird is diving vertically downward…
Idea: Apparent Distance in Two Media (Bird-Fish Problem)
New ideaHardNumerical value
JEE Main 202212 questions in 11 shifts
- 25 Jul, Shift 1Q46Time taken by light to travel in two different materials A and B of refractive indices and of same thickness is and…
Idea: Time of Flight in a Medium
New ideaMediumSingle correct - 26 Jul, Shift 2Q37Light travels in two media and with speeds and respectively. The…
Idea: Critical Angle Between Two Dense Media
New ideaEasySingle correct - 29 Jul, Shift 1Q59The X-Y plane be taken as the boundary between two transparent media and . in has a refractive index of…
Idea: Vector Form of Snell's Law
New ideaHardNumerical value - 29 Jul, Shift 2Q50Light enters from air into a given medium at an angle of with interface of the air-medium surface. After refraction, the light…
Idea: Deviation at a Single Interface
New ideaMediumSingle correct - 30 Jul, Shift 2Q22A ring is placed at the bottom of a trough containing four immiscible liquids of refractive indices 1.0, 2.0, 3.0 and 4.0 poured one above…
Idea: Apparent Depth and Shift
New ideaMediumNumerical value - 24 Jun, Shift 2Q57A ray of light is incident at an angle of incidence on the glass slab of refractive index . After refraction, the…
Idea: Lateral Shift in Slabs
New ideaMediumNumerical value - 25 Jun, Shift 1Q44A light wave travelling linearly in a medium of dielectric constant 4, incidents on the horizontal interface separating medium with air.…
Idea: Total Internal Reflection
Asked the year beforeMediumSingle correct - 25 Jun, Shift 1Q49The difference of speed of light in the two media A and B () is m/s. If the refractive index of medium B is 1.47,…
Idea: Refractive Index and Speed
New ideaMediumSingle correct - 26 Jun, Shift 2Q58A small bulb is placed at the bottom of a tank containing water to a depth of . The refractive index of water is…
Idea: Circle of Illuminance (Fish-Eye View)
New ideaMediumNumerical value - 27 Jun, Shift 1Q47Consider a light ray travelling in air is incident into a medium of refractive index . The incident angle is twice that of…
Idea: Snell's Law Application
MediumSingle correct - 27 Jun, Shift 2Q47If a wave gets refracted into a denser medium, then which of the following is true?
Idea: Invariance of Frequency in Refraction
New ideaEasySingle correct - 29 Jun, Shift 2Q34The speed of light in media ‘’ and ‘’ are 2.0 × and 1.5 × respectively. A ray of light enters from…
Idea: Critical Angle Between Two Dense Media
New ideaMediumSingle correct
JEE Main 20215 questions in 5 shifts
- 3 Aug, Shift 1Q15In the given figure, a ray of light passes through four transparent media with refractive indices , , and . The…
Idea: Normal Shift across Multiple Slabs
New ideaMediumDiagram based · figure - 22 Jul, Shift 2Q3A ray of light passes from a denser medium to a rarer medium at an angle of incidence . The reflected and refracted rays make an angle…
Idea: Total Internal Reflection
Asked the year beforeMediumSingle correct · figure - 25 Jul, Shift 1Q9A ray of laser of a wavelength 630 nm is incident at an angle of at the diamond-air interface. It is going from diamond to air.…
Idea: Total Internal Reflection
Asked the year beforeEasySingle correct - 25 Jul, Shift 2Q16A ray of light entering from air into a denser medium of refractive index , as shown in figure. The light ray suffers total…
Idea: Total Internal Reflection
Asked the year beforeMediumDiagram based · figure - 18 Mar, Shift 2Q17Three rays of light, namely red (R), green (G) and blue (B) are incident on the face PQ of a right angled prism PQR as shown in the…
Idea: Wavelength Dependence of TIR
New ideaMediumDiagram based · figure
JEE Main 20205 questions in 5 shifts
- 8 Jan, Shift 1Q15The critical angle of a medium for a specific wavelength, if the medium has relative permittivity 3 and relative permeability…
Idea: Total Internal Reflection
New ideaMediumSingle correct - 9 Jan, Shift 1Q15A vessel of depth 2h is half filled with a liquid of refractive index and the upper half with another liquid of refractive…
Idea: Apparent Depth of Immiscible Liquids
New ideaEasySingle correct - 9 Jan, Shift 2Q17There is a small source of light at some depth below the surface of water (refractive index ) in a tank of large cross…
Idea: Total Internal Reflection
New ideaHardSingle correct - 2 Sep, Shift 2Q25A light ray enters a solid glass sphere of refractive index at an angle of incidence 60°. The ray is both reflected and…
Idea: Partial Reflection and Refraction
New ideaMediumNumerical value - 3 Sep, Shift 1Q24An observer can see through a small hole on the side of a jar (radius 15 cm) at a point at height of 15 cm from the bottom (see figure).…
Idea: Snell's Law Application
New ideaHardNumerical value · figure
Questions from the official JEE Main Paper 1 shifts published by NTA (CBSE for 2017). Questions NTA dropped are left out. Topic and idea tags, counts and notes are Lumi’s.