Class 11 Physics MCQ Chapter 2 Units and Measurement
Are you looking for Class 11 Physics MCQ Chapter 2 Units and Measurement English Medium? If yes, then this article is an excellent study resource for AHSEC Higher Secondary First Year students. Here, you will find important multiple-choice questions (MCQs) with answers to help you prepare effectively for examinations.
The chapter Units and Measurement introduces the basic methods of measuring physical quantities in Physics. Students will learn about SI units, fundamental and derived units, dimensions, dimensional analysis, significant figures, accuracy, precision, errors in measurement, and scientific notation. These concepts are essential because they form the foundation for all numerical calculations and experiments in Physics.
The MCQs provided here are prepared according to the latest AHSEC syllabus and examination pattern. They help students revise important topics, improve problem-solving skills, and understand measurement techniques more clearly. Regular practice of these objective questions can enhance confidence and improve exam performance.
Whether you are preparing for class tests, annual examinations, or the AHSEC HS First Year Final Examination, these MCQ solutions will help you strengthen your concepts and achieve better results in Physics.
Part I
Class 11 Physics MCQ Chapter 2 Units and Measurement
VSA & MCQs
I. Very Short Answer (VSA) Questions with Answers
Q. What is a physical quantity?
Ans: A physical quantity is a quantity that can be measured and expressed with a number and a unit.
Q. What are fundamental quantities?
Ans: Fundamental quantities are independent physical quantities that cannot be derived from others.
Q. Name the seven SI base units.
Ans: metre (m), kilogram (kg), second (s), ampere (A), kelvin (K), mole (mol), candela (cd).
Q. What is the SI unit of length?
Ans: metre (m).
Q. What is the SI unit of mass?
Ans: kilogram (kg).
Q. What is the SI unit of time?
Ans: second (s).
Q. Define derived units.
Ans: Derived units are units obtained from fundamental units by mathematical combinations.
Q. What is a dimensional formula?
Ans: It is an expression showing the powers of fundamental quantities in a physical quantity.
Q. What is meant by least count?
Ans: Least count is the smallest measurement that an instrument can measure accurately.
Q. What is the least count of a metre scale?
Ans: 1 mm or 0.1 cm.
Q. What is parallax error?
Ans: The error caused due to improper positioning of the eye while taking measurements.
Q. Define significant figures.
Ans: Significant figures are meaningful digits in a measured quantity, including the uncertain digit.
Q. How many significant figures are there in 0.00520?
Ans: Three significant figures.
Q. What is the order of magnitude?
Ans: It is the power of 10 representing the size of a quantity.
Q. Name the instrument used to measure very small lengths accurately.
Ans: Screw gauge.
Q. What is the principle of dimensional homogeneity?
Ans: Both sides of a physical equation must have the same dimensions.
Q. What is random error?
Ans: Errors that occur irregularly due to unpredictable causes are called random errors.
Q. What is systematic error?
Ans: Errors that occur in a fixed pattern due to faulty instruments or methods.
Q. Can dimensional analysis derive numerical constants?
Ans: No, dimensional analysis cannot determine numerical constants.
II. Multiple Choice Questions (MCQs)
Q. Which of the following is a fundamental quantity?
(a) Force
(b) Velocity
(c) Length
(d) Density
Ans: (c) Length
Q. The SI unit of force is:
(a) Joule
(b) Newton
(c) Watt
(d) Pascal
Ans: (b) Newton
Q. Which instrument is used to measure the diameter of a wire accurately?
(a) Metre scale
(b) Vernier calipers
(c) Stopwatch
(d) Thermometer
Ans: (b) Vernier calipers
Q. The SI unit of pressure is:
(a) Newton
(b) Joule
(c) Pascal
(d) Dyne
Ans: (c) Pascal
Q. One kilometre is equal to:
(a) 10 m
(b) 100 m
(c) 1000 m
(d) 10000 m
Ans: (c) 1000 m
Q. Which of the following has no dimensions?
(a) Density
(b) Strain
(c) Force
(d) Work
Ans: (b) Strain
Q. The least count of a screw gauge is generally:
(a) 1 cm
(b) 1 mm
(c) 0.01 mm
(d) 1 m
Ans: (c) 0.01 mm
Q. The SI unit of energy is:
(a) Watt
(b) Newton
(c) Joule
(d) Pascal
Ans: (c) Joule
Q. Which one is not a scalar quantity?
(a) Mass
(b) Time
(c) Velocity
(d) Temperature
Ans: (c) Velocity
Q. The SI unit of power is:
(a) Joule
(b) Watt
(c) Newton
(d) Volt
Ans: (b) Watt
Q. The number of significant figures in 0.00340 is:
(a) 2
(b) 3
(c) 4
(d) 5
Ans: (b) 3
Q. Which error occurs due to faulty calibration?
(a) Random error
(b) Gross error
(c) Systematic error
(d) Human error
Ans: (c) Systematic error
Q. The SI unit of frequency is:
(a) Hertz
(b) Joule
(c) Newton
(d) Watt
Ans: (a) Hertz
Q. A light year is a unit of:
(a) Time
(b) Mass
(c) Distance
(d) Energy
Ans: (c) Distance
Q. Which of the following is a derived unit?
(a) metre
(b) kilogram
(c) second
(d) newton
Ans: (d) newton
Q. The SI unit of electric current is:
(a) Volt
(b) Coulomb
(c) Ampere
(d) Ohm
Ans: (c) Ampere
Q. Which instrument measures atmospheric pressure?
(a) Ammeter
(b) Barometer
(c) Hydrometer
(d) Lactometer
Ans: (b) Barometer
Q. The SI unit of temperature is:
(a) Celsius
(b) Fahrenheit
(c) Kelvin
(d) Joule
Ans: (c) Kelvin
Q. Which of the following is dimensionless?
(a) Relative density
(b) Force
(c) Pressure
(d) Energy
Ans: (a) Relative density
Q. The SI unit of luminous intensity is:
(a) Candela
(b) Mole
(c) Kelvin
(d) Ampere
Ans: (a) Candela
Q. Which among the following is used to measure small thickness?
(a) Beam balance
(b) Screw gauge
(c) Stopwatch
(d) Thermometer
Ans: (b) Screw gauge
Q. The SI unit of amount of substance is:
(a) Candela
(b) Mole
(c) Kelvin
(d) Newton
Ans: (b) Mole
Q. Which method is used to check the correctness of physical equations?
(a) Graph method
(b) Dimensional analysis
(c) Calculus
(d) Algebraic method
Ans: (b) Dimensional analysis
III. Assertion–Reason Type MCQs
Q. Assertion (A): Force is a derived quantity.
Reason (R): Force depends on mass and acceleration.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.
Ans: (a) Both A and R are true and R is the correct explanation of A.
Q. Assertion (A): Significant figures indicate measurement accuracy.
Reason (R): All zeros in a number are significant.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.
Ans: (c) A is true but R is false.
Q. Assertion (A): Dimensional analysis can verify physical equations.
Reason (R): Dimensions on both sides of an equation must be same.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.
Ans: (a) Both A and R are true and R is the correct explanation of A.
Q. Assertion (A): Parallax error can be avoided by keeping the eye vertically above the mark.
Reason (R): Incorrect eye position causes wrong reading.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.
Ans: (a) Both A and R are true and R is the correct explanation of A.
Q. Assertion (A): Velocity and speed have the same dimensions.
Reason (R): Both are measured in m/s.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.
Ans: (a) Both A and R are true and R is the correct explanation of A.
Q. Assertion (A): Relative density has no unit.
Reason (R): Relative density is the ratio of two similar quantities.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.
Ans: (a) Both A and R are true and R is the correct explanation of A.
Q. Assertion (A): One astronomical unit is used for measuring atomic distances.
Reason (R): An astronomical unit is a very large unit of length.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.
Ans: (d) A is false but R is true.
