What are JEE Laboratory Experiments Class 11 questions?

JEE Laboratory Experiments Class 11 questions test conceptual understanding of standard Physics experiments, including measuring instruments, experimental procedures, graph interpretation, error analysis, and the physical principles behind experiments.

Are Laboratory Experiments important for JEE Main?

Yes. Laboratory Experiments form an important part of the experimental skills section and typically contribute 1–2 direct conceptual questions in JEE Main.

Which Laboratory Experiments are most important for JEE?

The simple pendulum, vernier caliper, screw gauge, resonance tube, and experiments related to elasticity and mechanics are among the most frequently tested practical topics.

Is the Laboratory Experiments section easy for JEE?

Yes. This section is generally considered easy to moderate because most questions focus on experimental procedures, instrument usage, and conceptual understanding rather than lengthy calculations.

How many Laboratory Experiments questions come in JEE Main and Advanced?

JEE Main usually includes 1–2 questions from experimental skills and laboratory-based concepts, while JEE Advanced may incorporate experimental reasoning into data interpretation or conceptual questions.

How can I prepare Laboratory Experiments for JEE?

To prepare effectively, study each experiment systematically, learn instrument least counts, understand experimental procedures, revise graphs and observations, and solve previous year questions.

What are the most common mistakes in JEE Laboratory Experiment questions?

Students often misread instrument scales, confuse systematic and random errors, forget least count calculations, and incorrectly interpret experimental graphs and observations.

Which concepts are important in Laboratory Experiments for JEE?

Key concepts include least count calculations, error analysis, graph interpretation, significant figures, experimental procedures, and the working principles of common laboratory instruments such as the vernier caliper, screw gauge, and resonance tube.

JEE Laboratory Experiments - XI Questions

JEE Laboratory Experiments XI is a unique and often underestimated section in JEE Main that tests your understanding of standard Class 11 Physics experiments. Rather than asking you to perform the experiment, it probes your conceptual understanding of the procedure, sources of error, the instruments used, and the physical principles behind each experiment. Because these questions are direct and concept-based, JEE Laboratory Experiments XI questions are a reliable source of quick marks for aspirants who study them seriously. The Class 11 experiments covered include the use of vernier calipers and screw gauges for precise measurement, determination of the acceleration due to gravity using a simple pendulum, verification of Hooke's law using springs, finding the velocity of sound using a resonance tube, determining surface tension by capillary rise, measuring viscosity by Stokes' method, and studying refraction at a curved surface. Each experiment has a specific set of observable quantities, potential error sources, and graphical interpretations that JEE Main frequently targets. Practising topic-wise JEE Questions helps you learn to identify what each experiment actually measures and where errors are most likely.

A strong grasp of experimental physics also supports your theoretical understanding, since real physical phenomena are what the theory describes. Students who study experiments carefully develop a sharper sense of physical quantities, units, and measurement precision that benefits the entire Physics paper.

Laboratory Experiments XI Topic Overview

Parameter	Details
Topic Name	Laboratory Experiments XI
Subject	Physics
JEE Main Weightage	~2-4% (1-2 questions on average)
JEE Advanced Weightage	~2-3% (via experimental reasoning)
Difficulty Level	Easy to Moderate
Important Concepts	Vernier Caliper, Screw Gauge, Simple Pendulum, Resonance Tube, Hooke's Law
Recommended Practice Level	Moderate to High - attempt 50+ conceptual problems

Why Practice JEE Laboratory Experiments XI Questions?

Accessible marks: Most questions are direct and conceptual, making them quick to answer correctly.
Low calculation load: Understanding the experiment matters more than heavy computation.
Consistent weightage: JEE Main includes 1-2 experimental questions from Class 11 each year.
Improves physical intuition: Knowing how measurements are made deepens understanding of theory.
Error analysis skills: Practice sharpens your ability to identify systematic and random errors.
Graph interpretation: Experimental questions test graph-reading skills used across Physics.
Efficient revision: A defined list of Class 11 experiments makes the topic straightforward to master.

Important Concepts and Subtopics

Concept	Importance	Difficulty Level	Frequently Asked In
Vernier Caliper and Least Count	Very High	Easy-Moderate	JEE Main
Screw Gauge and Pitch	Very High	Easy-Moderate	JEE Main
Simple Pendulum and g Determination	Very High	Moderate	JEE Main & Advanced
Resonance Tube and Velocity of Sound	High	Moderate	JEE Main
Hooke's Law and Spring Constant	High	Moderate	JEE Main
Surface Tension by Capillary Rise	Moderate	Moderate	JEE Main
Viscosity by Stokes' Method	Moderate	Moderate	JEE Main
Sources of Error and Precautions	High	Easy	JEE Main

Preparation Strategy for JEE Laboratory Experiments XI

Concept learning: Study each experiment in a structured way: understand the physical quantity being measured, the instruments and their least counts, the formula relating observations to the result, and the main sources of error. Visualise the setup and the graph that results from plotting observations, since graph-based questions are common.

Formula revision: Keep the least-count formulas for the vernier caliper and screw gauge, the simple-pendulum time-period expression, the resonance-tube path-difference condition, and Stokes' law together for quick review. Organised JEE Study Material helps you compile experiment summaries, precautions, and error sources in one place for efficient revision.

Problem-solving techniques: For instrument questions, calculate the least count first, then use it to read the given scale. For pendulum and resonance problems, apply the relevant formula directly. For error questions, identify whether the error is systematic or random and what effect it has on the result.

Common mistakes: Misreading the least count formula, confusing the end correction in resonance tubes with the diameter of the tube, applying Stokes' law outside its validity range, and ignoring the backlash error in screw gauges.

Exam strategy: Treat Laboratory Experiments questions as quick wins. Approach them with confidence since they require understanding rather than heavy computation, and answer them early in the Physics section.

JEE Main and Advanced Weightage Analysis

Exam	Average Questions	Expected Marks
JEE Main	1-2	4-8
JEE Advanced	0-1 (via reasoning)	0-4

Laboratory Experiments XI contributes a small but consistent set of direct marks in JEE Main. In JEE Advanced, experimental reasoning appears through data interpretation and error analysis rather than specific instrument questions.

Tips to Solve Laboratory Experiments XI Questions Faster

Calculate the least count of the vernier caliper or screw gauge as the first step in any instrument question.
For the simple pendulum, remember that T is proportional to the square root of L and independent of amplitude for small oscillations.
Identify the antinodes in a resonance tube to apply the path-difference condition correctly.
Recognise that Stokes' law applies only when the object moves at terminal velocity through the fluid.
For Hooke's law questions, link the slope of the force-extension graph to the spring constant.
Identify whether an error increases or decreases the measured result to answer error-direction questions.

Practising these in a timed setting with a JEE Mock Test converts your knowledge of experiments into fast, accurate answers on exam day.

JEE Laboratory Experiments - XI Questions

Question 1

Two thin wires, Wire-1 of diameter $$0.650\,\mathrm{mm}$$ and Wire-2 of unknown diameter $$d$$ are given. To obtain the value of $$d$$, the diameters of the two wires are measured with a screw gauge. The screw gauge has a pitch of $$0.5\,\mathrm{mm}$$ and there are $$100$$ divisions on the circular scale (CS). The smallest division on the linear scale (LS) is $$0.5\,\mathrm{mm}$$. The table shows the readings of LS and CS for the measurements. The value of $$d$$ (in $$\mu\mathrm{m}$$) is:

	Readings
	LS (mm)	CS
Wire-1	0.5	42
Wire-2	1.5	95

Question 2

In a screw gauge, the zero of the circular scale lies 3 divisions above the horizontal pitch line when their metallic studs are brought in contact. Using this instrument thickness of a sheet is measured. If pitch scale reading is 1 mm and the circular scale reading is 51 then the correct thickness of the sheet is_____ mm.
[Assume least count is 0.01 mm]

1.48

1.54

1.50

1.51

Question 3

In a vernier callipers, 50 vernier scale divisions are equal to 48 main scale divisions. If one main scale division= 0.05 mm, then the least count of the vernier callipers is__________ mm.

0.05

0.02

0.002

0.005

Question 4

Surface tension of two liquids (having same densities), $$T_{1}$$ and $$T_{2}$$, are measured using capillary rise method utilizing two tubes with inner radii of $$r_{1}$$ and $$r_{2}$$
where $$r_{1} > r_{2}$$. The measured liquid heights in these tubes are $$h_{1}$$ and $$h_{2}$$ respectively. [Ignore the weight of the liquid about the lowest point of miniscus]. The heights $$h_{1}$$ and $$h_{2}$$ and surfaces tensions $$T_{1}$$ and $$T_{2}$$ satisfy the relation :

$$h_{1} = h_{2}$$ and $$T_{1} = T_{2}$$

$$h_{1} > h_{2}$$ and $$T_{1} < T_{2}$$

$$h_{1} < h_{2}$$ and $$T_{1} = T_{2}$$

$$h_{1} > h_{2}$$ and $$T_{1} = T_{2}$$

Question 5

When both jaws of vernier callipers touch each other, zero mark of the vernier scale is right to zero mark of main scale $$4^{th}$$ mark on vernier scale coincides with certain mark on the main scale. while measuring the length of a cylinder, observer observes 15 divisions on main scale and $$5^{th}$$ division of vernier scale coincides with a main scale division. Measured length of cylinder is______mm.
(Least count of Vernier calliper= 0.1 mm)

15.5

15.1

15.9

15.4

Question 1

Given below are two statements : Statement I : In a vernier callipers, one vernier scale division is always smaller than one main scale division. Statement II : The vernier constant is given by one main scale division multiplied by the number of vernier scale divisions. In the light of the above statements, choose the correct answer from the options given below.

Statement I is true but Statement II is false

Statement I is false but Statement II is true

Both Statement I and Statement II are false

Both Statement I and Statement II are true

Question 2

A tiny metallic rectangular sheet has length and breadth of 5 mm and 2.5 mm , respectively. Using a specially designed screw gauge which has pitch of 0.75 mm and 15 divisions in the circular scale, you are asked to find the area of the sheet. In this measurement, the maximum fractional error will be $$\frac{x}{100}$$ where x is __________.

Question 3

The least count of a screw gauge is $$0.01\,mm.$$ If the pitch is increased by $$75\%$$ and number of divisions on the circular scale is reduced by $$50\%,$$ the new least count will be $$\underline{\hspace{2cm}}\times10^{-3}\,mm.$$

Question 1

Identify compound (Z) in the following reaction sequence.

Question 2

Identify the product (P) in the following reaction:

Question 3

Match List - I with List - II.

Choose the correct answer from the options given below :

(A)-(IV), (B)-(III), (C)-(I), (D)-(II)

(A)-(II), (B)-(III), (C)-(IV), (D)-(I)

(A)-(IV), (B)-(I), (C)-(II), (D)-(III)

(A)-(III), (B)-(I), (C)-(IV), (D)-(II)

Question 4

Which among the following aldehydes is most reactive towards nucleophilic addition reactions?

Question 5

Identify major product "X" formed in the following reaction :

Question 6

Two moles of benzaldehyde and one mole of acetone under alkaline conditions using aqueous NaOH after heating gives $$x$$ as the major product. The number of $$\pi$$ bonds in the product $$x$$ is _____

Question 1

A spectrometer gives the following reading when used to measure the angle of a prism. Main scale reading: $$58.5$$ degree; Vernier scale reading: $$09$$ divisions. Given that $$1$$ division on main scale corresponds to $$0.5$$ degree. Total divisions on the vernier scale are $$30$$ and match with $$29$$ divisions of the main scale. The angle of the prism from the above data

$$58.59^\circ$$

$$58.77^\circ$$

$$58.65^\circ$$

$$59^\circ$$

Question 2

$$N$$ divisions on the main scale of a vernier calliper coincide with $$(N+1)$$ divisions of the vernier scale. If each division of main scale is $$a$$ units, then the least count of the instrument is

$$a$$

$$\frac{a}{N}$$

$$\frac{N}{N+1}\times a$$

$$\frac{a}{N+1}$$

Question 1

A screw gauge gives the following reading when used to measure the diameter of a wire. Main scale reading: $$0 \, \text{mm}$$. Circular scale reading: 52 divisions. Given that $$1 \, \text{mm}$$ on main scale corresponds to 100 divisions of the circular scale. The diameter of wire from the above data is:

$$0.052 \, \text{cm}$$

$$0.026 \, \text{cm}$$

$$0.005 \, \text{cm}$$

$$0.52 \, \text{cm}$$

Question 1

In an experiment the angles are required to be measured using an instrument. $$29$$ divisions of the main scale exactly coincide with the $$30$$ divisions of the vernier scale. If the smallest division of the main scale is half-a-degree $$(= 0.5°)$$, then the least count of the instrument is

one minute

half minute

one degree

half degree

Question 1

An experiment is performed to find the refractive index of glass using a travelling microscope. In this experiment distance are measured by

a vernier scale provided on the microscope

a standard laboratory scale

a meter scale provided on the microscope

a screw gauage provided on the microscope

Question 2

Shown in the figure below is a meter-bridge set up with null deflection in the galvanometer.
The value of the unknown resistor $$R$$ is

$$13.75\ \Omega$$

$$220\ \Omega$$

$$110\ \Omega$$

$$55\ \Omega$$

Question 3

Two full turns of the circular scale of a screw gauge cover a distance of 1 mm on its main scale. The total number of divisions on the circular scale is 50. Further, it is found that the screw gauge has a zero error of $$-0.03$$ mm while measuring the diameter of a thin wire, a student notes the main scale reading of 3 mm and the number of circular scale divisions in line with the main scale as 35. The diameter of the wire is

3.32 mm

3.73 mm

3.67 mm

3.38 mm

Solution

Solution & Explanation

1. Calculate the Pitch and Least Count (LC) of the Screw Gauge

The pitch of a screw gauge is defined as the distance advanced by the spindle per complete rotation of the circular scale. We are given that 2 full turns cover a distance of $$1 \,\, \text{mm}$$:

$$\text{Pitch} = \frac{\text{Distance covered on main scale}}{\text{Number of full rotations}} = \frac{1 \,\, \text{mm}}{2} = 0.5 \,\, \text{mm}$$

The Least Count (LC) is the smallest measurement that can be accurately taken using the instrument. It is calculated by dividing the pitch by the total number of divisions on the circular scale ($$50$$):

$$\text{Least Count (LC)} = \frac{\text{Pitch}}{\text{Total number of circular divisions}} = \frac{0.5 \,\, \text{mm}}{50} = 0.01 \,\, \text{mm}$$

2. Determine the Observed Reading

The total observed reading before adjusting for any systematic tool misalignment is calculated using the main scale reading (MSR) and the circular scale reading (CSR) matching line:

Main Scale Reading ($$\text{MSR}$$): $$3 \,\, \text{mm}$$
Circular Scale Reading ($$\text{CSR}$$): $$35 \,\, \text{divisions}$$

$$\text{Observed Reading} = \text{MSR} + (\text{CSR} \times \text{LC})$$

$$\text{Observed Reading} = 3 \,\, \text{mm} + (35 \times 0.01 \,\, \text{mm}) = 3 + 0.35 = 3.35 \,\, \text{mm}$$

3. Correct for Zero Error to Find True Diameter

The instrument is given to have a built-in zero error of $$-0.03 \,\, \text{mm}$$. To find the true, accurate thickness parameter, we must subtract this zero error from our raw observed calculation:

$$\text{True Diameter} = \text{Observed Reading} - (\text{Zero Error})$$

$$\text{True Diameter} = 3.35 \,\, \text{mm} - (-0.03 \,\, \text{mm})$$

$$\text{True Diameter} = 3.35 \,\, \text{mm} + 0.03 \,\, \text{mm} = 3.38 \,\, \text{mm}$$

Concept Check: Because the tool has a negative zero error, it sits slightly behind the true zero index mark when completely closed. As a result, it consistently under-reports measurements by $$0.03 \,\, \text{mm}$$. We mathematically add this value back to our observed measurement to calculate the correct structural thickness.

Correct Option Key: Option D ($$3.38 \,\, \text{mm}$$)

Question 1

In a metre bridge experiment null point is obtained at $$20$$ cm from one end of the wire when resistance $$X$$ is balanced against another resistance $$Y$$. If $$X < Y$$, then where will be the new position of the null point from the same end, if one decides to balance a resistance of $$4X$$ against $$Y$$?

$$50$$ cm

$$80$$ cm

$$40$$ cm

$$70$$ cm

JEE Laboratory Experiments - XI Questions

Laboratory Experiments XI Topic Overview

Why Practice JEE Laboratory Experiments XI Questions?

Important Concepts and Subtopics

Preparation Strategy for JEE Laboratory Experiments XI

JEE Main and Advanced Weightage Analysis

Tips to Solve Laboratory Experiments XI Questions Faster

JEE Laboratory Experiments - XI Questions

Solution & Explanation

1. Calculate the Pitch and Least Count (LC) of the Screw Gauge

2. Determine the Observed Reading

3. Correct for Zero Error to Find True Diameter

Frequently Asked Questions

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JEE Laboratory Experiments - XI Questions

Laboratory Experiments XI Topic Overview

Why Practice JEE Laboratory Experiments XI Questions?

Important Concepts and Subtopics

Preparation Strategy for JEE Laboratory Experiments XI

JEE Main and Advanced Weightage Analysis

Tips to Solve Laboratory Experiments XI Questions Faster

JEE Laboratory Experiments - XI Questions

Solution & Explanation

1. Calculate the Pitch and Least Count (LC) of the Screw Gauge

2. Determine the Observed Reading

3. Correct for Zero Error to Find True Diameter

Frequently Asked Questions

JEE Mains Question Bank & Mock Tests

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