PHYSICS

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2nd EDITION

I SBN SYLLABUS COVERED

YEAR 2021-22

"978-93-5423-619-8"

ICSE-INDIAN CERTIFICATE OF SECONDARY EDUCATION EXAMINATION

PUBLISHED BY

COPYRIG HT

RESERVED BY THE PUBLISHERS

All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, without written permission from the publishers. The author and publisher will gladly receive information enabling them to rectify any error or omission in subsequent editions.

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DI SCL A IMER

Oswaal Books has exercised due care and caution in collecting all the data before publishing this book. In spite of this, if any omission, inaccuracy or printing error occurs with regard to the data contained in this book, Oswaal Books will not be held responsible or liable. Oswaal Books will be grateful if you could point out any such error or offer your suggestions which will be of great help for other readers. 2) Printed at Upkar( Printing Unit, Agra

TABLE OF CONTENTS l l

Latest Syllabus issued by CISCE for Academic Year 2021-2022 Supplement : New Topics Introduced by CISCE for 2021-22 Exam Unitwise Self Assessment Papers

1.

Measurements and Experimentation



Topic 2. Simple Pendulum

l l



2.

3.

Examination Paper - 2020 (Issued by CISCE)

Topic 1. International System of Units Motion in one Dimension

Topic 1. Scalar and Vector Quantities, Distance, Displacement Topic 2. Speed, Velocity, Acceleration, Equations of Motion Laws of Motion

Topic 1. Contact and Non-Contact Forces Topic 3. Gravitation

Topic 1. Pressure in Fluids and Its Transmission

5.

Heat and Energy



Topic 2. Archimedes' Principle and Law of Floatation Topic 1. Concepts of Heat and Temperature

Topic 2. Global Warming and Green House Effect

6. Light

Topic 1. Reflection of Light Topic 2. Spherical Mirrors

7. Sound

Topic 1. Nature of Sound Waves

8.

Electricity and Magnetism



11 - 20

21 - 36

Topic 2. Newton’s Laws of Motion





43 - 47 1 - 10

4. Fluids

8 - 11 13 - 33 34 - 42

37 - 54

55 - 60

61 - 76

77 - 84

Topic 2. Infrasonic and Ultrasonic Waves

85 - 95

Topic 1. Electric Circuit Topic 2. Magnetism

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LET THE ADVENTURE BEGIN!

The new way of learning; Blended Learning The pandemic introduced us all to a phenomenon which now seems to be the way forward for learners & teachers alike, it is blended learning. In just a span of a year, we have witnessed a rapid advancement in e-learning. Many researchers say that, in no time e-learning will become mainstream. Oswaal Books identified this as an opportunity and thus we decided to prepare students for this turbulent yet a very useful change, hence this book is a hybrid edition. Through this hybrid edition, we aim to help the students learn at their own pace. Hence, we wish to make learning adaptive in order to simplify it for every student.

India is currently one of the youngest economies in the world. Hence, it’s imperative for our education system to churn out more learners than ever before. It is this ‘learner’s mindset’ which will set us apart from the rest of the world. Through Education, we must sow the seeds of Curiosity today to reap the benefits of Intellect tomorrow.

What Oswaal Question Banks have for you? It is exciting to finally see new innovations in learning all over the country. The structural changes in Education that are being brought in by the new National Educational Policy (NEP) resonate with our approach of focusing on deeper understanding instead of rote learning. We have designed this book to make learning simpler for every student. Our cognitive and innovative exercises like the Mind Maps make us the leaders of simplified learning. Our study material proves to be so effective because it is based on Bloom’s Taxonomy and also helps retain information for a longer period of time. The last year saw a sudden rise in the need for online classes and self-study. So as blended learning replaces traditional learning methods, Oswaal Books provide the right material to adapt and learn faster. This book takes an intuitive approach for skill development to unleash a student’s maximum potential. All the latest Typologies of Questions; based on the board’s Specimen Paper 2020-21, have been exclusively developed by the Oswaal Editorial Board to help students master every form of question.

Our Heartfelt Gratitude! e have taken due care in developing this book. There have been a lot of people who have helped W us in our journey. We would like to offer heartfelt gratitude to them- our authors, editors, reviewers, and especially students like you who regularly send us suggestions which help us in continuous improvement of this book. Here are the names of the students who have helped us make this book better: 1. Disha from Patna

6. Utkarsh from Bnagalore

2. Bhoomi from Patna

7. Vaibhav from Chennai

3. Ruslaan from Mumbai

8. Vansh from Jaipur

4. Alekh from Pune

9. Pratham from Lucknow

5. Nirali from Delhi

10. Prastuti from Kanpur

Wish you all Happy Learning and a Successful 2021-22!!

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SYLLABUS Latest Syllabus for Academic year 2021-22

PHYSICS CLASS IX SCIENCE Paper - 1 Aims: (i) To acquire knowledge and understanding of the terms, facts, concepts, definitions, laws, principles and processes of Physics. (ii) To develop skills in practical aspects of handling apparatus, recording observations and in drawing diagrams, graphs, etc. (iii) To develop instrumental, communication, deductive and problem-solving skills. (iv) To discover that there is a living and growing physics relevant to the modern age in which we live. There will be one paper of two hours duration carrying 80 marks and Internal Assessment of practical work carrying 20 marks.

time; equations of uniformly accelerated motion with derivations.

The paper will be divided into two sections, Section I (40 marks) and Section II (40 marks).

Examples of Scalar and vector quantities only, rest and motion in one dimension; distance and displacement; speed and velocity; acceleration and retardation; distance-time and velocity-time graphs; meaning of slope of the graphs; [Non-uniform acceleration excluded].

Section I (compulsory) will contain short answer questions on the entire syllabus. Section II will contain six questions. Candidates will be required to answer any four of these six questions.

Equations to be derived: v = u + at;

Note: Unless otherwise specified, only SI Units are to be used while teaching and learning, as well as for answering questions.

S = ut + ½at2; S = ½(u+v)t; v2 = u2 + 2aS. [Equation for Snth is not included].

1. Measurements and Experimentation

Simple numerical problems.

(i) International System of Units, the required SI units with correct symbols are given at the end of this syllabus. Other commonly used system of units - fps and cgs.

3. Laws of Motion (i) Contact and non-contact forces; cgs & SI units.

(ii) Measurements using common instruments, Vernier callipers and micro-metre screw gauge for length, and simple pendulum for time.

Measurement of length using, Vernier callipers and micro-metre screw gauge. Decreasing leastcount leads to an increase in accuracy; leastcount (LC) of Vernier callipers and screw gauge), zero error (basic idea), (no numerical problems on callipers and screw gauge), Simple pendulum: time period, frequency, graph of length l versus T2 only; slope of the graph. Formula T=2.p.

1

g

(ii) Newton’s First Law of Motion (qualitative discussion) introduction of the idea of inertia, mass and force.

[no

derivation]. Only simple numerical problems.

Examples of contact forces (frictional force, normal reaction force, tension force as applied through strings and force exerted during collision) and non-contact forces (gravitational, electric and magnetic). General properties of non-contact forces. cgs and SI units of force and their relation with Gravitational units.

Newton's first law; statement and qualitative discussion; definitions of inertia and force from first law, examples of inertia as illustration of first law. (Inertial mass not included).

(iii) Newton’s Second Law of Motion (including F=ma); weight and mass.

2. Motion in One Dimension Scalar and vector quantities, distance, speed, velocity, acceleration; graphs of distance-time and speed-



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Detailed study of the second law. Linear momentum, p = mv; change in momentum Dp = Δ(mn) =

SYLLABUS the fraction of volume of the body immersed; (ρ1/ρ2 = V2/V1); apparent weight of floating object; application to ship, submarine, iceberg, balloons, etc.

mΔv for mass remaining constant, rate of change of momentum;





Δ p/Δ t = mΔv /Δt = ma or {



p2 − p1 mv − mu m( v − u) = = = ma ;}; t t t



Simple numerical problems combining



F = Δp /Δt = ma and equations of motion. Units of force - only cgs and SI.

(iv) Newton’s Third Law of Motion (qualitative discussion only); simple examples.

Statement with qualitative discussion; examples of action - reaction pairs, (FBA and FAB); action and reaction always act on different bodies.

(v) Gravitation

Universal Law of Gravitation. (Statement and equation) and its importance. Gravity, acceleration due to gravity, free fall. Weight and mass, Weight as force of gravity comparison of mass and weight; gravitational units of force, (Simple numerical problems), (problems on variation of gravity excluded)

4. Fluids (i) Change of pressure with depth (including the formula p=hρg); Transmission of pressure in liquids; atmospheric pressure.

Thrust and Pressure and their units; pressure exerted by a liquid column p = hρg; simple daily life examples, (i) broadness of the base of a dam, (ii) Diver’s suit etc. some consequences of p = hρg; transmission of pressure in liquids; Pascal's law; examples; atmospheric pressure; common manifestation and consequences. Variations of pressure with altitude, (qualitative only); applications such as weather forecasting and altimeter. (Simple numerical problems)

(ii) Buoyancy, Archimedes’ Principle; floatation; relationship with density; relative density; determination of relative density of a solid. Buoyancy, upthrust (FB); definition; different cases, FB>, = or < weight W of the body immersed; characteristic properties of upthrust; Archimedes’ principle; explanation of cases where bodies with density ρ >, = or < the density ρ' of the fluid in which it is immersed.

Relative Density (RD) and Archimedes’ principle. Experimental determination of RD of a solid and liquid denser than water. Floatation: principle of floatation; relation between the density of a floating body, density of the liquid in which it is floating and

Simple numerical problems involving Archimedes’ principle, buoyancy and floatation. 5. Heat and Energy (i) Concepts of heat and temperature. Heat as energy, SI unit – joule, 1 cal = 4.186 J exactly. (ii) Anomalous expansion of water; graphs showing variation of volume and density of water with temperature in the 0 to 10 0C range. Hope’s experiment and consequences of Anomalous expansion. (iii) Energy flow and its importance: Understanding the flow of energy as Linear and linking it with the laws of Thermodynamics‘Energy is neither created nor destroyed’ and ‘No Energy transfer is 100% efficient. (iv) Energy sources. Solar, wind, water and nuclear energy (only qualitative discussion of steps to produce electricity). Renewable versus non-renewable sources (elementary ideas with example). Renewable energy: biogas, solar energy, wind energy, energy from falling of water, run-of-the river schemes, energy from waste, tidal energy, etc. Issues of economic viability and ability to meet demands. Non-renewable energy – coal, oil, natural gas. Inequitable use of energy in urban and rural areas. Use of hydro electrical powers for light and tube wells. (v) Global warming and Green House effect. Meaning, causes and impact on the life on earth. Projections for the future; what needs to be done. Energy degradation – meaning and examples. 6. Light (i) Reflection of light; images formed by a pair of parallel and perpendicular plane mirrors; Laws of reflection; experimental verification; characteristics of images formed in a pair of mirrors, (a) parallel and (b) perpendicular to each other; uses of plane mirrors. (ii) Spherical mirrors; characteristics of image formed by these mirrors. Uses of concave and convex mirrors. (Only simple direct ray diagrams are required). Brief introduction to spherical mirrors - concave and

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SYLLABUS convex mirrors, centre and radius of curvature, pole and principal axis, focus and focal length; location of images from ray diagram for various positions of a small linear object on the principal axis of concave and convex mirrors; characteristics of images.

f = R/2 (without proof); sign convention and direct numerical problems using the mirror formulae are included. (Derivation of formulae not required)



Uses of spherical mirrors.



Scale drawing or graphical representation of ray diagrams not required.

(ii) Induced magnetism,Magnetic field of earth. Neutral points in magnetic fields.

(i) Nature of Sound waves. Requirement of a medium for sound waves to travel; propagation and speed in different media; comparison with speed of light. Sound propagation, terms – frequency (f), wavelength (λ), velocity (V), relation V = fλ. (Simple numerical problems) effect of different factors on the speed of sound; comparison of speed of sound with speed of light; consequences of the large difference in these speeds in air; thunder and lightning. (ii) Infrasonic, sonic, ultrasonic frequencies and their applications. Elementary ideas and simple applications only. Difference between ultrasonic and supersonic. 8. Electricity and Magnetism (i) Simple electric circuit using an electric cell and a bulb to introduce the idea of current (including its relationship to charge); potential difference; insulators and conductors; closed and open circuits; direction of current (electron flow and conventional) Current Electricity: brief introduction of sources of direct current - cells, accumulators (construction, working and equations excluded); Electric current as the rate of flow of electric charge (direction of current - conventional and electronic), symbols used in circuit diagrams. Detection of current by Galvanometer or ammeter (functioning of the meters not to be introduced). Idea of electric circuit by using cell, key, resistance wire/resistance box/rheostat, qualitatively.; elementary idea about work done in transferring charge through a conductor wire; potential difference V = W/q.



(No derivation of formula) simple numerical problems.



Social initiatives: Improving efficiency of existing technologies and introducing new eco-friendly technologies. Creating awareness and building trends

Magnetism: magnetism induced by bar magnets on magnetic materials; induction precedes attraction; lines of magnetic field and their properties; evidences of existence of earth’s magnetic field, magnetic compass. Uniform magnetic field of earth and non-uniform field of a bar magnet placed along magnetic north-south; neutral point; properties of magnetic field lines.

(iii) Introduction of electromagnet and its uses.

7. Sound



of sensitive use of resources and products, e.g. reduced use of electricity.

Self-explanatory. INTERNAL ASSESSMENT OF PRACTICAL WORK

Candidates will be asked to carry out experiments for which instructions are given. The experiments may be based on topics that are not included in the syllabus but theoretical knowledge will not be required. A candidate will be expected to be able to follow simple instructions, to take suitable readings and to present these readings in a systematic form. He/she may be required to exhibit his/her data graphically. Candidates will be expected to appreciate and use the concepts of least count, significant figures and elementary error handling. A set of 6 to 10 experiments may be designed as given below or as found most suitable by the teacher. Students should be encouraged to record their observations systematically in a neat tabular form - in columns with column heads including units or in numbered rows as necessary. The final result or conclusion may be recorded for each experiment. Some of the experiments may be demonstrated (with the help of students) if these cannot be given to each student as lab experiments.

1. Determine the least count of the Vernier callipers and measure the length and diameter of a small cylinder (average of three sets) - may be a metal rod of length 2 to 3 cm and diameter 1 to 2 cm. 2. Determine the pitch and least count of the given screw gauge and measure the mean radius of the given wire, taking three sets of readings in perpendicular directions. 3. Measure the length, breadth and thickness of a glass block using a metre rule (each reading correct to a mm), taking the mean of three readings in each case. Calculate the volume of the block in cm3 and m3. Determine the mass (not

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SYLLABUS weight) of the block using any convenient balance in g and kg. Calculate the density of glass in cgs and SI units using mass and volume in the respective units. Obtain the relation between the two density units. 4. Measure the volume of a metal bob (the one used in simple pendulum experiments) from the readings of water level in a measuring cylinder using displacement method. Also calculate the same volume from the radius measured using Vernier callipers. Comment on the accuracies. 5. Obtain five sets of readings of the time taken for 20 oscillations of a simple pendulum of lengths about 70, 80, 90, 100 and 110 cm; calculate the time periods (T) and their squares (T2) for each length (l). Plot a graph of l vs. T2. Draw the best - fit straight - line graph. Also, obtain its slope. Calculate the value of g in the 2 laboratory. It is 4π x slope. 6. Take a beaker of water. Place it on the wire gauze on a tripod stand. Suspend two thermometers - one with Celsius and the other with Fahrenheit scale. Record the thermometer readings at 5 to 7 different temperatures. You may start with ice-cold water, then allow it to warm up and then heat it slowly taking temperature (at regular intervals) as high as possible. Plot a graph of TF vs. TC. Obtain the slope. Compare with the theoretical value. Read the intercept on TF axis for TC = 0. 7. Using a plane mirror strip mounted vertically on a board, obtain the reflected rays for three rays incident at different angles. Measure the angles of incidence and angles of reflection. See if these angles are equal. 8. Place three object pins at different distances on a line perpendicular to a plane mirror fixed vertically on a board. Obtain two reflected rays (for each pin) fixing two pins in line with the image. Obtain the positions of the images in each case by extending backwards (using dashed lines), the lines representing reflected rays. Measure the object distances and image distances in the three cases. Tabulate. Are they equal? Generalize the result.

9. Obtain the focal length of a concave mirror (a) by distant object method, focusing its real image on a screen or wall and (b) by one needle method removing parallax or focusing the image of the illuminated wire gauze attached to a ray box. One could also improvise with a candle and a screen. Enter your observations in numbered rows. 10. Connect a suitable dc source (two dry cells or an acid cell), a key and a bulb (may be a small one used in torches) in series. Close the circuit by inserting the plug in the key. Observe the bulb as it lights up. Now open the circuit, connect another identical bulb in between the first bulband the cell so that the two bulbs are in series. Close the key. Observe the lighted bulbs How does the light from any one bulb compare with that in the first case when you had only one bulb? Disconnect the second bulb. Reconnect the circuit as in the first experiment. Now connect the second bulb across the first bulb. The two bulbs are connected in parallel. Observe the brightness of any one bulb. Compare with previous results. Draw your own conclu sions regarding the current and resistance in the three cases. 11. Plot the magnetic field lines of earth (without any magnet nearby) using a small compass needle. On another sheet of paper, place a bar magnet with its axis parallel to the magnetic lines of the earth, i.e. along the magnetic meridian or magnetic north south. Plot the magnetic field in the region around the magnet. Identify the regions where the combined magnetic field of the magnet and the earth is (a) strongest, (b) very weak but not zero, and (c) zero. Why is neutral point, so called? 12. Using a spring balance obtain the weight (in N) of a metal ball in air and then completely immersed in water in a measuring cylinder. Note the volume of the ball from the volume of the water displaced. Calculate the upthrust from the first two weights. Also calculate the mass and then weight of the water displaced by the bob M=V.ρ, W=mg). Use the above result to verify Archimedes principle.

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Arc Radius Area • Solid angle = r²

O

l

Graph between T² and l

(iii) Time period of oscillation does not depend on the mass of the body. 2 • Graph of square of time period (T ) with the length (l) of a pendulum is obtained as a straight line.

T²

Types

Simple pendulum to measure time

• The work function of pendulum clock is based on periodic oscillations of a pendulum T=2 l g 1 (i) T   l (ii) T g 

Relationship between time period and frequency 1 f= 1 or T= f T

• Plane angle, =

ng

Unit



Second Level

Trace the Mind Map First Level

es

nt

p Ty

Co u

Le ast Third Level

t ni lu

it

m

un it

Supplem ent

d un rive e D

Comparison with a certain internationally accepted reference standard is called unit.

es

Typ

Common Measuring instruments

Measurements and Experimentation

Physical Quantities

i an



Fu

• The quantities which are independent of other quantities • Length(L), Mass(M), Time(T), Electric Current (A), Temperature (), Luminous Intensity(cd), Amount of substance(md).

Me

Sy



a

n d am en t

• The quantities which depend on fundamental quantities are called derived quantities. • Area, volume , acceleration.

ary

Least Count

Least Count

0.1 mm

0.01 mm

• Quantities for plane angle and solid angle have radian and steradian as units.

• Set of fundamental and derived units CGS – Centimeter, Gram, Second FPS –Foot, Pound, Second MKS – Meter, Kilogram, Second S.I. –System International

un it

• The units which are derived from fundamental units are called derived units. • Physical quantity like speed, acceleration have derived units like m/s , m/s².

• The units which are independent of any other units are called fundamental units. • Meter, Kilogram, Second, Ampere, Kelvin, Candela and Mole are fundamental units.

Vernier Calliper

Screw Gauge

Smallest Measurement an instrument can measure .

SUPPLEMENT |

ste

13

New Topics introduced by CISCE for 2021-22 Exam

PHYSICS Chapter 1 : Measurements and Experimentation





TOPIC - 3 Measurement Using Common Instruments

Revision Notes  The least count of an instrument is the smallest measurement that can be taken accurately with it.  The smaller the least count of an instrument, the more precise is the measurement made by using it.  A Vernier caliper is a device used to measure the length or width of any small object with greater precision.  Pierre Vernier invented the vernier caliper.  Vernier Caliper uses two scales for measurements.

o The fixed scale also called the main scale.



o The Vernier scale which slides along the main scale.

 The Least Count of Vernier is also called the Vernier Constant.

Scan to know more about this topic

Vernier Calipers

 L.C. Vernier Caliper = Value of 1 main scale division – Value of 1 Vernier scale division  The Least Count of a Vernier Caliper is normally 0.1 mm.  Length of the object = Total reading = Main scale reading + Vernier reading  L.C. of Vernier Caliper = Value of 1 main scale division / Total number of divisions on Vernier scale

Scan to know more about this topic

 The distance between the zero of the main scale and the vernier scale is called Zero Error.  Two Kinds of Zero Error:

o Positive Zero Error



o Negative Zero Error

Screw Gauge

 On bringing both jaws together, if zero of Vernier Scale is in right of the zero of the main scale then it is called Positive Zero Error.  On bringing both jaws together, if zero of Vernier Scale is in right of the zero of the main scale then it is called Negative Zero Error.  Correct Reading = Observed reading – Zero Reading (With Sign)  A screw gauge is an instrument used for measuring the diameter of a thin wire or the thickness of a sheet of metal.  The pitch of a screw gauge is the distance moved by the screw along its axis in one complete rotation of its head.  Pitch of Screw Gauge = Unit length on main scale/Number of divisions in a unit length  Generally, the pitch of a screw is 1 mm or 0.5 mm.

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 The least count of a screw gauge is the smallest distance moved by the tip of the screw gauge, when the circular scale of it moves by one division.  Least Count of Screw Gauge = Pitch of screw/Total number of divisions on the circular scale  Error due to wear and tear of the screw is called Backlash Error.

Know the Terms  Less the least count of an instrument, more the accuracy of the Instrument.  Correction of positive zero error is said to be negative.  Correction of negative zero error is said to be positive.  Backlash error can be avoided by rotating the screw in only one direction.

2 Marks Questions Q. 1. What do you understand by the term least count? Explain with an example. Ans. The least count of an instrument is the smallest measurement that can be taken accurately with it. For ex: If a measuring scale has 10 divisions between 0 cm and 1 cm, then its Least Count is 1 cm / 10 = 1 mm. That means it can measure up to a value of 1 mm accurately. Q. 2. Give two uses of Vernier Caliper. Ans. Two uses of Vernier Caliper are:

Ans. A common Vernier caliper can measure the length up to two decimal places if it is being measured in cm. As it has precision up to 0.1 mm or 0.01 cm.

Commonly Made Error  Students usually get confused in 0.1 mm or 0.01 cm.

Answering Tip  Always remember it as 0.1 mm and then it can be converted into cm. Most of the time one has to answer in mm only.



(a) Measuring length of an Object.

Q. 7. Write two uses of Screw Gauge.



(b) Measuring the diameter of any spherical, circular or cylindrical objects.

Ans. (a) To find the diameter of a steel rod or wire.

Q. 3. What is Vernier constant? Ans. The Least count of a Vernier Caliper is called its Vernier constant. The Least Count of a Vernier Caliper is normally 0.1 mm. Q. 4. What are the functions of the Main scale and Vernier scale in Vernier caliper?



(b) To measure the thickness of a metallic sheet.

Q. 8. When is a vernier caliper said to be free from zero error? Ans. A vernier caliper is said to be free from zero error, if the zero of the vernier scale coincides with the zero of the main scale. Q. 9. What is the purpose of a ratchet in a screw gauge?

Ans. The main scale can measure length correctly up to 1 mm. Whereas the Vernier scale helps to measure the length correctly up to 0.1 mm.

Ans. The ratchet is used in a screw gauge to hold the object under measurement gently between the studs.

Q. 5. Write the functions of strip and Vernier scale in Vernier caliper.

Q. 10. Which of the following measures a small length to a high accuracy: meter scale, vernier calipers, screw gauge?

Ans. Strip helps to measure the depth and diameter. Whereas the Vernier scale acts as the main scale with a precision of 0.1 mm. Q. 6. Up to how many decimal places can a common vernier caliper measure the length in cm?

Ans. Screw gauge has the lowest least count among all of them, so it can measure a small length to high accuracy.

3 Marks Questions Q. 1. What do you understand by zero error in Vernier caliper? Also, explain its types in detail.

Ans. If on bringing the movable and fixed jaws of vernier caliper together, the zero of vernier scale doesn’t coincide with the zero of the main scale