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1. Which of the following is a base quantity in the International System of Units (SI)?
ⓐ. Volume
ⓑ. Mass
ⓒ. Speed
ⓓ. Force
Correct Answer: Mass
Explanation: In the International System of Units (SI), mass is considered a base quantity. The base unit for mass in the SI system is the kilogram. Volume, speed, and force are derived quantities.
2. What is the SI unit for measuring electric current?
ⓐ. Volt
ⓑ. Ampere
ⓒ. Coulomb
ⓓ. Ohm
Correct Answer: Ampere
Explanation: The SI unit for measuring electric current is the ampere, which is one of the seven base units in the International System of Units (SI). Volt, coulomb, and ohm are related to electric potential, electric charge, and electrical resistance, respectively.
3. Which instrument is used to measure very small lengths with high accuracy?
ⓐ. Ruler
ⓑ. Vernier Caliper
ⓒ. Micrometer Screw Gauge
ⓓ. Tape Measure
Correct Answer: Micrometer Screw Gauge
Explanation: A micrometer screw gauge is used to measure very small lengths or thicknesses with high accuracy. It is more precise than a vernier caliper or a ruler and is often used in mechanical engineering and machining applications.
4. What is the value of one nanometer in meters?
ⓐ. \( 10^{-6} \) meters
ⓑ. \( 10^{-9} \) meters
ⓒ. \( 10^{-12} \) meters
ⓓ. \( 10^{-15} \) meters
Correct Answer: \( 10^{-9} \) meters
Explanation: One nanometer is equal to \( 10^{-9} \) meters. It is a unit of length commonly used to measure dimensions at the atomic or molecular scale.
5. Which of the following quantities has the dimension \([M][L][T^{-2}]\)?
ⓐ. Velocity
ⓑ. Acceleration
ⓒ. Force
ⓓ. Energy
Correct Answer: Force
Explanation: The dimension of force in terms of mass (M), length (L), and time (T) is \([M][L][T^{-2}]\). This is derived from Newton’s second law of motion, where force is the product of mass and acceleration.
6. Which of the following is not a derived unit in the SI system?
ⓐ. Newton
ⓑ. Joule
ⓒ. Pascal
ⓓ. Kilogram
Correct Answer: Kilogram
Explanation: Kilogram is a base unit in the SI system, representing mass. Newton, joule, and pascal are derived units used to measure force, energy, and pressure, respectively.
7. What is the principle behind the functioning of a Vernier caliper?
ⓐ. Differential measurement
ⓑ. Optical magnification
ⓒ. Electromagnetic induction
ⓓ. Vernier scale
Correct Answer: Vernier scale
Explanation: A Vernier caliper functions based on the principle of the Vernier scale, which allows users to measure lengths with higher precision by providing an additional scale for finer readings.
8. Which of the following units is used to measure solid angle?
ⓐ. Radian
ⓑ. Degree
ⓒ. Steradian
ⓓ. Gradient
Correct Answer: Steradian
Explanation: The unit used to measure solid angles is the steradian. It is the SI unit for measuring three-dimensional angular spans. Radian is used for planar angles.
9. What is the main advantage of using the metric system for scientific measurements?
ⓐ. It is based on multiples of 5
ⓑ. It uses historical units of measurement
ⓒ. It provides a consistent decimal-based system
ⓓ. It incorporates units from different systems
Correct Answer: It provides a consistent decimal-based system
Explanation: The main advantage of the metric system is its consistency and use of a decimal-based system, making conversions simpler and more systematic.
10. Which of the following errors is a type of systematic error?
ⓐ. Random error
ⓑ. Instrumental error
ⓒ. Human error
ⓓ. Zero error
Correct Answer: Instrumental error
Explanation: Instrumental error is a type of systematic error caused by inaccuracies in the measuring instrument. Systematic errors consistently cause measurements to deviate in the same direction, unlike random errors, which vary unpredictably.
11. Why are measurements essential in scientific experiments?
ⓐ. To make experiments more complex
ⓑ. To verify the results and theories
ⓒ. To ensure experiments are expensive
ⓓ. To increase the number of variables
Correct Answer: To verify the results and theories
Explanation: Measurements are crucial in scientific experiments because they provide quantitative data that can be used to verify the results and validate or refute scientific theories. Accurate measurements ensure the reliability and reproducibility of experiments.
12. What is the role of a standard unit of measurement in science?
ⓐ. To complicate scientific calculations
ⓑ. To allow uniformity and consistency
ⓒ. To reduce the accuracy of measurements
ⓓ. To eliminate the need for conversions
Correct Answer: To allow uniformity and consistency
Explanation: The role of a standard unit of measurement in science is to ensure uniformity and consistency in measurements across different experiments and studies. This standardization allows scientists to compare results accurately and reliably.
13. How does precision differ from accuracy in measurements?
ⓐ. Precision is about how close measurements are to the true value; accuracy is about consistency
ⓑ. Precision and accuracy are the same concepts
ⓒ. Precision is about consistency; accuracy is about how close measurements are to the true value
ⓓ. Precision is irrelevant in scientific measurements
Correct Answer: Precision is about consistency; accuracy is about how close measurements are to the true value
Explanation: Precision refers to the consistency of repeated measurements, while accuracy refers to how close a measurement is to the true or accepted value. Both are important for reliable scientific data.
14. What is a derived quantity in the context of measurements?
ⓐ. A quantity that is directly measured
ⓑ. A quantity that is obtained by combining base quantities
ⓒ. A quantity with no unit
ⓓ. A quantity that cannot be measured
Correct Answer: A quantity that is obtained by combining base quantities
Explanation: A derived quantity is obtained by combining base quantities through multiplication or division. Examples include velocity (derived from length and time) and force (derived from mass and acceleration).
15. What is the importance of significant figures in scientific measurements?
ⓐ. They make the measurements longer
ⓑ. They indicate the precision of a measurement
ⓒ. They increase the error margin
ⓓ. They are used only in theoretical physics
Correct Answer: They indicate the precision of a measurement
Explanation: Significant figures in a measurement indicate its precision and help in understanding the reliability of the measured value. They include all the known digits plus one estimated digit.
16. Which of the following best describes a systematic error?
ⓐ. An error that varies randomly
ⓑ. An error that consistently occurs in the same direction
ⓒ. An error due to human mistakes
ⓓ. An error that cannot be corrected
Correct Answer: An error that consistently occurs in the same direction
Explanation: A systematic error is a consistent, repeatable error associated with faulty equipment or a flawed experiment design. It can often be identified and corrected.
17. In which of the following ways does the measurement system help in international scientific communication?
ⓐ. By creating different standards for each country
ⓑ. By using the metric system as a common language
ⓒ. By eliminating the need for conversions
ⓓ. By allowing arbitrary units
Correct Answer: By using the metric system as a common language
Explanation: The metric system, or International System of Units (SI), acts as a common language in science, facilitating clear and precise communication of measurements and results across the global scientific community.
18. What is the purpose of calibration in measurement instruments?
ⓐ. To reduce the cost of instruments
ⓑ. To introduce random errors
ⓒ. To ensure the accuracy and reliability of measurements
ⓓ. To complicate the measurement process
Correct Answer: To ensure the accuracy and reliability of measurements
Explanation: Calibration is the process of adjusting and standardizing a measurement instrument to ensure its accuracy and reliability. It helps in providing correct and consistent measurements over time.
19. Which of the following is a consequence of using inaccurate measurements in scientific research?
ⓐ. Accurate results
ⓑ. Reliable conclusions
ⓒ. Inconsistent and unreliable data
ⓓ. Improved experiment design
Correct Answer: Inconsistent and unreliable data
Explanation: Using inaccurate measurements in scientific research leads to inconsistent and unreliable data, which can result in incorrect conclusions and affect the credibility of the research findings.
20. Why is it important to have multiple measurements in an experiment?
ⓐ. To increase the error margin
ⓑ. To ensure reproducibility and accuracy
ⓒ. To reduce the number of data points
ⓓ. To make the analysis more difficult
Correct Answer: To ensure reproducibility and accuracy
Explanation: Multiple measurements in an experiment help in ensuring reproducibility and accuracy. They allow for averaging out random errors and provide a more reliable estimate of the true value.
21. Which of the following is a fundamental quantity in the SI system?
ⓐ. Volume
ⓑ. Time
ⓒ. Speed
ⓓ. Force
Correct Answer: Time
Explanation: Time is a fundamental quantity in the SI system with the base unit second (s). Volume, speed, and force are derived quantities, which are expressed in terms of fundamental quantities.
22. What is the SI base unit for the quantity of substance?
ⓐ. Mole
ⓑ. Gram
ⓒ. Liter
ⓓ. Molecule
Correct Answer: Mole
Explanation: The SI base unit for the quantity of substance is the mole. One mole represents Avogadro’s number (approximately \(6.022 \times 10^{23}\)) of particles, such as atoms, molecules, or ions.
23. Which derived quantity has the SI unit of meters per second squared (m/s\(^2\))?
ⓐ. Velocity
ⓑ. Acceleration
ⓒ. Force
ⓓ. Momentum
Correct Answer: Acceleration
Explanation: Acceleration is the derived quantity that has the SI unit of meters per second squared (m/s\(^2\)). Velocity is measured in meters per second (m/s), force in newtons (N), and momentum in kilogram meters per second (kg·m/s).
24. What is the derived unit for the quantity of force in the SI system?
ⓐ. Joule
ⓑ. Newton
ⓒ. Pascal
ⓓ. Watt
Correct Answer: Newton
Explanation: The derived unit for force in the SI system is the newton (N). One newton is the force required to accelerate a one-kilogram mass by one meter per second squared.
25. Which fundamental quantity does the derived quantity ‘energy’ depend on?
ⓐ. Mass, length, and time
ⓑ. Length and time only
ⓒ. Mass and temperature
ⓓ. Electric current and luminous intensity
Correct Answer: Mass, length, and time
Explanation: The derived quantity energy depends on the fundamental quantities of mass, length, and time. The SI unit for energy is the joule, which is defined as one kilogram meter squared per second squared (\(\text{kg} \cdot \text{m}^2/\text{s}^2\)).
26. Which of the following is a derived quantity in the SI system?
ⓐ. Electric current
ⓑ. Temperature
ⓒ. Luminous intensity
ⓓ. Power
Correct Answer: Power
Explanation: Power is a derived quantity in the SI system, with the unit watt (W), which is equivalent to joules per second (J/s). Electric current, temperature, and luminous intensity are fundamental quantities.
27. What is the SI derived unit for pressure?
ⓐ. Pascal
ⓑ. Bar
ⓒ. Atmosphere
ⓓ. Torr
Correct Answer: Pascal
Explanation: The SI derived unit for pressure is the pascal (Pa), which is defined as one newton per square meter (\(N/m^2\)). Other units like bar, atmosphere, and torr are non-SI units of pressure.
28. Which of the following pairs correctly matches a derived quantity with its corresponding SI unit?
ⓐ. Velocity – Meter
ⓑ. Volume – Liter
ⓒ. Force – Newton
ⓓ. Time – Second
Correct Answer: Force – Newton
Explanation: Force is a derived quantity, and its corresponding SI unit is the newton (N). Velocity is measured in meters per second (m/s), volume in cubic meters (m\(^3\)), and time in seconds (s).
29. Which fundamental quantity is involved in defining the derived unit of electrical resistance?
ⓐ. Mass
ⓑ. Length
ⓒ. Temperature
ⓓ. Electric current
Correct Answer: Electric current
Explanation: Electrical resistance is a derived quantity defined as the ratio of voltage to current, with the unit ohm (Ω), which involves the fundamental quantity of electric current.
30. What is the significance of derived quantities in scientific measurements?
ⓐ. They simplify the measurement process
ⓑ. They provide additional details about fundamental quantities
ⓒ. They represent combinations of fundamental quantities
ⓓ. They are less accurate than fundamental quantities
Correct Answer: They represent combinations of fundamental quantities
Explanation: Derived quantities are significant because they represent combinations of fundamental quantities, allowing scientists to express complex physical concepts and relationships in a standardized manner.
31. Which fundamental quantity is measured in kilograms (kg)?
ⓐ. Length
ⓑ. Mass
ⓒ. Time
ⓓ. Temperature
Correct Answer: Mass
Explanation: The kilogram (kg) is the SI base unit for mass, one of the fundamental quantities. Length is measured in meters (m), time in seconds (s), and temperature in kelvin (K).
32. Which derived quantity is measured in joules (J)?
ⓐ. Power
ⓑ. Force
ⓒ. Energy
ⓓ. Pressure
Correct Answer: Energy
Explanation: Energy is a derived quantity measured in joules (J). Power is measured in watts (W), force in newtons (N), and pressure in pascals (Pa).
33. Which of the following is a unit of the derived quantity of velocity?
ⓐ. Meter
ⓑ. Meter per second
ⓒ. Meter per second squared
ⓓ. Newton
Correct Answer: Meter per second
Explanation: Velocity is a derived quantity measured in meters per second (m/s). It describes the rate of change of position with respect to time.
34. What is the SI unit for the derived quantity of work?
ⓐ. Joule
ⓑ. Newton
ⓒ. Watt
ⓓ. Pascal
Correct Answer: Joule
Explanation: Work is a derived quantity measured in joules (J). One joule is equivalent to one newton-meter (N·m).
35. Which fundamental quantity is involved in defining the derived unit of frequency?
ⓐ. Mass
ⓑ. Time
ⓒ. Length
ⓓ. Electric current
Correct Answer: Time
Explanation: Frequency is a derived quantity that involves the fundamental quantity of time. It is measured in hertz (Hz), which is the reciprocal of time (s^-1).
36. Which of the following derived quantities is measured in pascals (Pa)?
ⓐ. Energy
ⓑ. Force
ⓒ. Pressure
ⓓ. Power
Correct Answer: Pressure
Explanation: Pressure is a derived quantity measured in pascals (Pa), defined as force per unit area (N/m^2).
37. Which of the following represents a correct pair of a fundamental quantity and its corresponding unit?
ⓐ. Electric current – Coulomb
ⓑ. Luminous intensity – Lumen
ⓒ. Temperature – Kelvin
ⓓ. Length – Liter
Correct Answer: Temperature – Kelvin
Explanation: Temperature is a fundamental quantity with the unit kelvin (K). Electric current is measured in amperes (A), luminous intensity in candelas (cd), and length in meters (m).
38. Which derived quantity is defined as the rate of doing work?
ⓐ. Force
ⓑ. Power
ⓒ. Energy
ⓓ. Pressure
Correct Answer: Power
Explanation: Power is defined as the rate of doing work and is measured in watts (W), where one watt equals one joule per second (J/s).
39. Which of the following is the SI unit for the derived quantity of electric charge?
ⓐ. Coulomb
ⓑ. Volt
ⓒ. Ampere
ⓓ. Ohm
Correct Answer: Coulomb
Explanation: Electric charge is a derived quantity measured in coulombs (C). It represents the quantity of electricity transported in one second by a current of one ampere.
40. What is the significance of base units in the SI system?
ⓐ. They simplify all measurements
ⓑ. They are independent and form the basis for all other units
ⓒ. They are more accurate than derived units
ⓓ. They eliminate the need for calibration
Correct Answer: They are independent and form the basis for all other units
Explanation: Base units in the SI system are independent and form the foundation for all other derived units. They provide a standardized reference for measuring fundamental quantities such as length, mass, time, and electric current.
41. Which ancient civilization is credited with developing one of the earliest systems of measurement?
ⓐ. Greek
ⓑ. Roman
ⓒ. Egyptian
ⓓ. Chinese
Correct Answer: Egyptian
Explanation: The ancient Egyptians developed one of the earliest systems of measurement, using body parts like fingers, palms, and cubits for length measurements.
42. Who introduced the concept of a standardized system of weights and measures in ancient times?
ⓐ. Babylonians
ⓑ. Greeks
ⓒ. Romans
ⓓ. Chinese
Correct Answer: Babylonians
Explanation: The Babylonians introduced the concept of a standardized system of weights and measures, with units such as the shekel and the mina.
43. Which ancient civilization used a decimal system of measurement?
ⓐ. Egyptian
ⓑ. Greek
ⓒ. Chinese
ⓓ. Roman
Correct Answer: Chinese
Explanation: The ancient Chinese used a decimal system of measurement, which influenced their units for length, weight, and volume.
44. Who developed the first known unit of length based on body parts?
ⓐ. Greeks
ⓑ. Egyptians
ⓒ. Romans
ⓓ. Chinese
Correct Answer: Egyptians
Explanation: The Egyptians developed the cubit, one of the first known units of length based on the length of the arm from the elbow to the tip of the middle finger.
45. Which civilization developed a standardized system of coinage that influenced early measurements?
ⓐ. Greeks
ⓑ. Romans
ⓒ. Egyptians
ⓓ. Chinese
Correct Answer: Greeks
Explanation: The Greeks developed a standardized system of coinage, including the drachma, which influenced their early measurements of weight and currency.
46. Who introduced the concept of the metric system during the French Revolution?
ⓐ. Napoleon Bonaparte
ⓑ. Louis XVI
ⓒ. Maximilien Robespierre
ⓓ. The French National Convention
Correct Answer: The French National Convention
Explanation: The National Convention legally established the metric system in 1795 (Loi du 18 germinal an III).
47. Which scientist was instrumental in promoting the adoption of the metric system internationally?
ⓐ. Isaac Newton
ⓑ. Galileo Galilei
ⓒ. Antoine Lavoisier
ⓓ. Albert Einstein
Correct Answer: Antoine Lavoisier
Explanation: Antoine Lavoisier, a French chemist, was instrumental in promoting the adoption of the metric system internationally during the late 18th century.
48. In which year did the Metric Act introduce the metric system in the United Kingdom?
ⓐ. 1776
ⓑ. 1814
ⓒ. 1864
ⓓ. 1971
Correct Answer: 1864
Explanation: The Metric Weights and Measures Act 1864 first permitted metric units in UK trade; later acts expanded usage.
49. Which international organization oversees the standardization and adoption of the metric system?
ⓐ. International Organization for Standardization (ISO)
ⓑ. United Nations Educational, Scientific and Cultural Organization (UNESCO)
ⓒ. Bureau International des Poids et Mesures (BIPM)
ⓓ. World Health Organization (WHO)
Correct Answer: Bureau International des Poids et Mesures (BIPM)
Explanation: The Bureau International des Poids et Mesures (BIPM), located in France, oversees the standardization and adoption of the metric system globally.
50. What was the significance of the Treaty of the Meter signed in 1875?
ⓐ. It established the metric system as the standard for international trade
ⓑ. It defined the fundamental units of the metric system
ⓒ. It created the International Bureau of Weights and Measures (BIPM) and international prototypes for the metre and kilogram
ⓓ. It unified all measurement systems into a single global standard
Correct Answer: It created the International Bureau of Weights and Measures (BIPM) and international prototypes for the metre and kilogram
Explanation: The Metre Convention founded BIPM/CIPM/CGPM and the metre–kilogram prototypes; it did not define all base units.
51. Why is it important to use standard units in scientific measurements?
ⓐ. To make calculations easier
ⓑ. To ensure consistency and comparability
ⓒ. To impress peers
ⓓ. To reduce costs
Correct Answer: To ensure consistency and comparability
Explanation: Standard units ensure that measurements can be consistently compared across different experiments, locations, and times, ensuring reliability in scientific data.
52. Which of the following is a consequence of using non-standard units in scientific measurements?
ⓐ. Increased accuracy
ⓑ. Improved reproducibility
ⓒ. Difficulty in comparing results
ⓓ. Simplified data analysis
Correct Answer: Difficulty in comparing results
Explanation: Non-standard units can lead to difficulty in comparing results from different experiments or researchers, as there is no universal basis for measurement.
53. What role do standard units play in international trade and commerce?
ⓐ. They reduce trade barriers
ⓑ. They increase tariffs
ⓒ. They eliminate taxes
ⓓ. They promote economic growth
Correct Answer: They reduce trade barriers
Explanation: Standard units facilitate international trade and commerce by providing a common basis for measuring quantities such as weight, volume, and length, thereby reducing trade barriers.
54. Which organization is responsible for maintaining and updating the International System of Units (SI)?
ⓐ. International Standards Organization (ISO)
ⓑ. Bureau International des Poids et Mesures (BIPM)
ⓒ. United Nations Educational, Scientific and Cultural Organization (UNESCO)
ⓓ. World Trade Organization (WTO)
Correct Answer: Bureau International des Poids et Mesures (BIPM)
Explanation: The Bureau International des Poids et Mesures (BIPM) is responsible for maintaining and updating the International System of Units (SI) to ensure uniformity and accuracy in measurement standards globally.
55. How do standard units contribute to scientific advancements?
ⓐ. By enabling reproducibility of experimental results
ⓑ. By reducing the need for experimentation
ⓒ. By simplifying theoretical calculations
ⓓ. By decreasing research funding
Correct Answer: By enabling reproducibility of experimental results
Explanation: Standard units enable scientists to reproduce experimental results accurately across different laboratories and studies, which is crucial for validating scientific theories and advancing knowledge.
56. Why do engineers and manufacturers use standard units in product design?
ⓐ. To increase production costs
ⓑ. To improve product quality
ⓒ. To reduce market demand
ⓓ. To complicate manufacturing processes
Correct Answer: To improve product quality
Explanation: Engineers and manufacturers use standard units to ensure that products meet specifications and can be assembled and used correctly anywhere in the world, thus improving product quality and reliability.
57. Which sector benefits most from the use of standard units in everyday applications?
ⓐ. Healthcare
ⓑ. Agriculture
ⓒ. Construction
ⓓ. Entertainment
Correct Answer: Healthcare
Explanation: The healthcare sector benefits significantly from the use of standard units to ensure accurate diagnosis, treatment, and medication dosages, which are critical for patient safety and health outcomes.
58. In what way do standard units support environmental sustainability efforts?
ⓐ. By reducing resource consumption
ⓑ. By increasing pollution levels
ⓒ. By promoting deforestation
ⓓ. By accelerating climate change
Correct Answer: By reducing resource consumption
Explanation: Standard units help measure resource consumption accurately, facilitating efforts to reduce waste, conserve energy, and promote sustainable practices in industry and daily life.
59. How do standard units contribute to international collaboration in scientific research?
ⓐ. By encouraging competition
ⓑ. By fostering trust and cooperation
ⓒ. By limiting research opportunities
ⓓ. By promoting political conflicts
Correct Answer: By fostering trust and cooperation
Explanation: Standard units foster trust and cooperation among researchers and nations by providing a common language for sharing data, collaborating on experiments, and advancing scientific knowledge globally.
60. What is the primary benefit of using standard units in education?
ⓐ. To increase tuition fees
ⓑ. To simplify grading systems
ⓒ. To enhance learning outcomes
ⓓ. To decrease school attendance
Correct Answer: To enhance learning outcomes
Explanation: Using standard units in education ensures that students and educators have a common understanding of measurements, which facilitates clear communication and effective teaching. Standard units help in comparing and contrasting data accurately, conducting experiments with consistency, and reducing confusion. This standardization enhances learning outcomes by providing a reliable framework for learning and assessment.
61. How do standard units contribute to effective communication in scientific literature?
ⓐ. By promoting ambiguity
ⓑ. By ensuring clarity and precision
ⓒ. By limiting publication opportunities
ⓓ. By encouraging plagiarism
Correct Answer: By ensuring clarity and precision
Explanation: Standard units ensure that scientific literature is clear and precise, facilitating effective communication of experimental methods, results, and conclusions among researchers.
62. Which aspect of standard units makes them essential for regulatory compliance?
ⓐ. They complicate regulatory requirements
ⓑ. They ensure consistent adherence to standards
ⓒ. They increase administrative costs
ⓓ. They facilitate compliance monitoring
Correct Answer: They facilitate compliance monitoring
Explanation: Standard units facilitate regulatory compliance by providing clear benchmarks for measuring and monitoring adherence to safety, quality, and environmental standards.
63. Why do international organizations advocate for the universal adoption of standard units?
ⓐ. To encourage cultural diversity
ⓑ. To promote economic inequality
ⓒ. To facilitate global cooperation
ⓓ. To hinder technological advancements
Correct Answer: To facilitate global cooperation
Explanation: Universal adoption of standard units promotes global cooperation by establishing a common framework for scientific research, trade, healthcare, and environmental protection across diverse cultures and nations.
64. How do standard units contribute to public health initiatives?
ⓐ. By increasing disease prevalence
ⓑ. By improving healthcare access
ⓒ. By promoting unhealthy lifestyles
ⓓ. By reducing life expectancy
Correct Answer: By improving healthcare access
Explanation: Standard units support public health initiatives by ensuring accurate measurement and reporting of health data, facilitating effective disease prevention, treatment, and healthcare planning.
65. Which field benefits from the use of standard units to ensure safe and efficient transportation?
ⓐ. Law enforcement
ⓑ. Education
ⓒ. Aerospace engineering
ⓓ. Agriculture
Correct Answer: Aerospace engineering
Explanation: Aerospace engineering relies on standard units to design and manufacture aircraft, spacecraft, and related systems, ensuring safety, reliability, and compliance with international aviation standards.
66. How do standard units contribute to consumer protection and fair trade practices?
ⓐ. By promoting price discrimination
ⓑ. By ensuring product quality and quantity
ⓒ. By limiting consumer choices
ⓓ. By increasing market monopolies
Correct Answer: By ensuring product quality and quantity
Explanation: Standard units protect consumers by ensuring that products are accurately labeled with standard measurements of quantity, weight, volume, and quality, promoting fair trade practices and consumer rights.
67. Which global initiative promotes the use of standard units for sustainable development goals?
ⓐ. Paris Agreement
ⓑ. Millennium Development Goals
ⓒ. Kyoto Protocol
ⓓ. Sustainable Development Goals
Correct Answer: Sustainable Development Goals
Explanation: The Sustainable Development Goals (SDGs) promote the use of standard units to measure progress toward global targets for poverty reduction, environmental sustainability, health, education, and economic development.
68. Why are standard units crucial for advancing technological innovations?
ⓐ. They hinder technological advancements
ⓑ. They promote outdated technologies
ⓒ. They ensure compatibility and interoperability
ⓓ. They discourage research and development
Correct Answer: They ensure compatibility and interoperability
Explanation: Standard units facilitate technological innovations by ensuring that new technologies, products, and systems are compatible, interoperable, and can be integrated seamlessly into existing infrastructure and networks.
69. How do standard units contribute to disaster preparedness and response efforts?
ⓐ. By increasing vulnerability
ⓑ. By reducing emergency response times
ⓒ. By promoting panic and chaos
ⓓ. By causing natural disasters
Correct Answer: By reducing emergency response times
Explanation: Standard units support disaster preparedness and response efforts by enabling accurate measurement and assessment of disaster impacts, coordinating emergency response activities, and allocating resources effectively.
70. What is the educational benefit of teaching students about standard units?
ⓐ. To discourage critical thinking
ⓑ. To limit academic achievements
ⓒ. To enhance scientific literacy
ⓓ. To decrease student motivation
Correct Answer: To enhance scientific literacy
Explanation: Teaching students about standard units is fundamental to developing their scientific literacy. It helps them understand and apply consistent measurement systems, which is crucial for conducting experiments, interpreting data, and communicating scientific findings. Standard units form the basis for comparing results and verifying experiments, thus fostering a deeper understanding of scientific principles and encouraging critical thinking and problem-solving skills.
71. What is the full form of SI units?
ⓐ. System of Inertial Units
ⓑ. Standard of International Units
ⓒ. System of International Units
ⓓ. Standardized Inertial Units
Correct Answer: System of International Units
Explanation: SI units stand for “Système International d’Unités,” which translates to “System of International Units” in English.
72. How many base SI units are there in the International System of Units?
ⓐ. 5
ⓑ. 6
ⓒ. 7
ⓓ. 8
Correct Answer: 7
Explanation: There are 7 base SI units: meter (length), kilogram (mass), second (time), ampere (electric current), kelvin (temperature), mole (amount of substance), and candela (luminous intensity).
73. Which SI base unit measures the amount of a substance?
ⓐ. Mole
ⓑ. Kelvin
ⓒ. Candela
ⓓ. Ampere
Correct Answer: Mole
Explanation: The mole is the SI base unit that measures the amount of a substance. It is used in chemistry to quantify the number of atoms, molecules, or ions in a sample.
74. What fundamental physical constant is used to define the meter in the SI system?
ⓐ. Speed of light
ⓑ. Planck constant
ⓒ. Boltzmann constant
ⓓ. Avogadro constant
Correct Answer: Speed of light
Explanation: The meter is defined in the SI system based on the speed of light in a vacuum, which is approximately 299,792,458 meters per second.
75. Which SI unit is defined based on the amount of electric charge flowing per unit time?
ⓐ. Volt
ⓑ. Ampere
ⓒ. Ohm
ⓓ. Coulomb
Correct Answer: Ampere
Explanation: The ampere is the SI unit of electric current, defined as the amount of electric charge flowing per unit time through a conductor when a current of one ampere is sustained.
76. What is the SI unit of luminous intensity?
ⓐ. Lux
ⓑ. Candela
ⓒ. Lumen
ⓓ. Watt
Correct Answer: Candela
Explanation: The candela is the SI unit of luminous intensity, measuring the amount of light emitted in a particular direction.
77. Which SI base unit is used to measure the amount of heat?
ⓐ. Kelvin
ⓑ. Joule
ⓒ. Watt
ⓓ. Mole
Correct Answer: Joule
Explanation: The joule is the SI unit of energy and heat. It is defined as the work done or energy transferred when a force of one newton acts over a distance of one meter.
78. What is the SI unit of electric potential difference?
ⓐ. Volt
ⓑ. Ampere
ⓒ. Ohm
ⓓ. Watt
Correct Answer: Volt
Explanation: The volt is the SI unit of electric potential difference or electromotive force, measuring the potential difference between two points in a circuit.
79. Which SI unit measures the amount of substance in a given mass of a substance?
ⓐ. Kelvin
ⓑ. Mole
ⓒ. Candela
ⓓ. Ampere
Correct Answer: Mole
Explanation: The mole is the SI unit used to measure the amount of substance in a given mass. It provides a way to count atoms or molecules by expressing their amount.
80. What is the SI unit of luminous flux?
ⓐ. Lux
ⓑ. Candela
ⓒ. Lumen
ⓓ. Watt
Correct Answer: Lumen
Explanation: The lumen is the SI unit of luminous flux, measuring the total quantity of visible light emitted by a source per unit of time.
81. Which SI base unit measures the intensity of a sound wave?
ⓐ. Watt per square meter (W/m²)
ⓑ. Hertz
ⓒ. Decibel
ⓓ. Watt
Correct Answer: Watt per square meter (W/m²)
Explanation: Sound intensity is power per area, SI unit $\mathrm{W\,m^{-2}}$. Decibel is a logarithmic level (not an SI unit), and “watt” alone is power, not intensity.
82. Which SI base unit measures the amount of electric charge?
ⓐ. Ampere
ⓑ. No SI base unit; charge is measured in coulomb (derived)
ⓒ. Ohm
ⓓ. Volt
Correct Answer: No SI base unit; charge is measured in coulomb (derived)
Explanation: Charge $Q$ has derived unit coulomb $(\mathrm{C})$, with $Q=I\,t$. The base unit is ampere for current.
83. What is the SI base unit for measuring the amount of substance?
ⓐ. Mole
ⓑ. Kelvin
ⓒ. Candela
ⓓ. Hertz
Correct Answer: Mole
Explanation: The mole (mol) is the SI base unit for measuring the amount of substance, defined as the amount of substance that contains as many elementary entities as there are atoms in 0.012 kilograms of carbon-12.
84. Which SI base unit measures the temperature of a system?
ⓐ. Kelvin
ⓑ. Joule
ⓒ. Watt
ⓓ. Meter
Correct Answer: Kelvin
Explanation: The kelvin (K) is the SI base unit for measuring temperature, defined based on the triple point of water (273.16 K).
85. Which SI base unit measures the intensity of an electric current?
ⓐ. Volt
ⓑ. Ampere
ⓒ. Ohm
ⓓ. Watt
Correct Answer: Ampere
Explanation: The ampere (A) is the SI base unit that measures the intensity of an electric current, defined as the flow of electric charge per unit time.
86. What is the SI base unit for measuring the luminous intensity of light?
ⓐ. Lux
ⓑ. Candela
ⓒ. Lumen
ⓓ. Watt
Correct Answer: Candela
Explanation: The candela (cd) is the SI base unit for measuring the luminous intensity of light emitted in a particular direction.
87. Which SI base unit measures the time taken by an event?
ⓐ. Second
ⓑ. Meter
ⓒ. Kilogram
ⓓ. Ampere
Correct Answer: Second
Explanation: The second (s) is the SI base unit that measures the time taken by an event, defined as the duration of 9,192,631,770 periods of the radiation corresponding to the transition between two hyperfine levels of the ground state of cesium-133 atom.
88. What is the SI base unit for measuring the length of an object?
ⓐ. Kilogram
ⓑ. Meter
ⓒ. Second
ⓓ. Candela
Correct Answer: Meter
Explanation: The meter (m) is the SI base unit for measuring the length of an object, defined as the distance traveled by light in vacuum in 1/299,792,458 seconds.
89. Which SI base unit measures the amount of light emitted by a source?
ⓐ. Watt
ⓑ. Candela
ⓒ. Lux
ⓓ. Joule
Correct Answer: Candela
Explanation: The candela (cd) is the SI base unit for measuring the amount of light emitted in a particular direction by a source.
90. What is the SI base unit for measuring the mass of an object?
ⓐ. Kilogram
ⓑ. Gram
ⓒ. Pound
ⓓ. Newton
Correct Answer: Kilogram
Explanation: The kilogram (kg) is the SI base unit for measuring the mass of an object, defined as the mass of the International Prototype of the Kilogram, a platinum-iridium cylinder kept at the International Bureau of Weights and Measures (BIPM) in France.
91. Which SI prefix represents \(10^{-3}\)?
ⓐ. Kilo-
ⓑ. Milli-
ⓒ. Centi-
ⓓ. Mega-
Correct Answer: Milli-
Explanation: Milli- is the SI prefix that represents \(10^{-3}\), meaning one-thousandth of a unit.
92. What is the value of the SI prefix centi-?
ⓐ. \(10^{-2}\)
ⓑ. \(10^{-3}\)
ⓒ. \(10^{2}\)
ⓓ. \(10^{3}\)
Correct Answer: \(10^{-2}\)
Explanation: Centi- is the SI prefix that represents \(10^{-2}\), meaning one-hundredth of a unit.
93. Which SI prefix denotes \(10^{6}\)?
ⓐ. Kilo-
ⓑ. Milli-
ⓒ. Mega-
ⓓ. Micro-
Correct Answer: Mega-
Explanation: Mega- is the SI prefix that denotes \(10^{6}\), meaning one million of a unit.
94. What is the value of the SI prefix micro-?
ⓐ. \(10^{-6}\)
ⓑ. \(10^{6}\)
ⓒ. \(10^{-9}\)
ⓓ. \(10^{9}\)
Correct Answer: \(10^{-6}\)
Explanation: Micro- is the SI prefix that represents \(10^{-6}\), meaning one millionth of a unit.
95. Which SI prefix signifies \(10^{-9}\)?
ⓐ. Nano-
ⓑ. Kilo-
ⓒ. Giga-
ⓓ. Milli-
Correct Answer: Nano-
Explanation: Nano- is the SI prefix that signifies \(10^{-9}\), meaning one billionth of a unit.
96. What is the value of the SI prefix giga-?
ⓐ. \(10^{6}\)
ⓑ. \(10^{12}\)
ⓒ. \(10^{-6}\)
ⓓ. \(10^{9}\)
Correct Answer: \(10^{9}\)
Explanation: Giga- is the SI prefix that represents \(10^{9}\), meaning one billion of a unit.
97. Which SI prefix denotes \(10^{-12}\)?
ⓐ. Pico-
ⓑ. Kilo-
ⓒ. Tera-
ⓓ. Micro-
Correct Answer: Pico-
Explanation: Pico- is the SI prefix that denotes \(10^{-12}\), meaning one trillionth of a unit.
98. What is the value of the SI prefix tera-?
ⓐ. \(10^{12}\)
ⓑ. \(10^{9}\)
ⓒ. \(10^{-12}\)
ⓓ. \(10^{6}\)
Correct Answer: \(10^{12}\)
Explanation: Tera- is the SI prefix that represents \(10^{12}\), meaning one trillion of a unit.
99. Which SI prefix signifies \(10^{-15}\)?
ⓐ. Femto-
ⓑ. Kilo-
ⓒ. Mega-
ⓓ. Milli-
Correct Answer: Femto-
Explanation: Femto- is the SI prefix that signifies \(10^{-15}\), meaning one quadrillionth of a unit.
100. What is the value of the SI prefix kilo-?
ⓐ. \(10^{3}\)
ⓑ. \(10^{-3}\)
ⓒ. \(10^{6}\)
ⓓ. \(10^{-6}\)
Correct Answer: \(10^{3}\)
Explanation: Kilo- is the SI prefix that represents \(10^{3}\), meaning one thousand of a unit.
Welcome to Class 11 Physics MCQs – Chapter 2: Units and Measurements (Part 1). This page is a chapter-wise question bank for the NCERT/CBSE Class 11 Physics syllabus—built for quick revision and exam speed. Practice MCQs / objective questions / Physics quiz items with solutions and explanations, ideal for CBSE Boards, JEE Main, NEET, competitive exams, and Board exams.
These MCQs are suitable for international competitive exams—physics concepts are universal.
Navigation & pages: The full chapter has 398 MCQs in 4 parts (100 + 100 + 100 + 98). Part 1 contains 100 MCQs split across 10 pages—you’ll see 10 questions per page. Use the page numbers above to view the remaining questions.
What you will learn & practice
- Introduction to Units and Measurements
- International System of Units (SI): base, derived, and supplementary units
- Measurement of Length, Mass, and Time (methods & devices)
- Accuracy & Precision of instruments and errors in measurement (systematic, random, least-count)
- Significant Figures: rules, rounding-off, operations with sig figs
- Dimensions of physical quantities and Dimensional Analysis (checking equations, finding relations, converting units)
How this practice works
- Click an option to check instantly: green dot = correct, red icon = incorrect. The Correct Answer and brief Explanation then appear.
- Use the 👁️ Eye icon to reveal the answer with explanation without guessing.
- Use the 📝 Notebook icon as a temporary workspace while reading (notes are not saved).
- Use the ⚠️ Alert icon to report a question if you find any mistake—your message reaches us instantly.
- Use the 💬 Message icon to leave a comment or start a discussion for that question.
Real value: Strictly aligned to NCERT/CBSE topics, informed by previous-year paper trends, and written with concise, exam-oriented explanations—perfect for one-mark questions, quick concept checks, and last-minute revision.
The full chapter includes 398 solved multiple-choice questions in 4 parts. This page (Part 1) gives the first 100 MCQs with answers and explanations to build your foundations. Explore more with: Class 11 Physics – Chapter Index, Class 11 – Subject Index, All Classes – MCQ Library.
- 👉 Total MCQs in this chapter: 398 (100 + 100 + 100 + 98)
- 👉 This page: first 100 multiple-choice questions with answers & brief explanations (in 10 pages)
- 👉 Best for: Boards • JEE/NEET • chapter-wise test • one-mark revision • quick Physics quiz
- 👉 Next: use the Part buttons and the page numbers above to continue
FAQs On Units and Measurements MCQS▼
▸ What are Units and Measurements MCQs in Class 11 Physics?
These are multiple-choice questions from Chapter 2 of NCERT Class 11 Physics – Units and Measurements. They test understanding of physical quantities, SI units, measurement errors, significant figures, and dimensional analysis.
▸ How many MCQs are available in this chapter?
There are a total of 398 MCQs from Units and Measurements. They are divided into 4 sets – three sets of 100 questions each and one set of 98 questions.
▸ Are these MCQs useful for NCERT and CBSE board exams?
Yes, these MCQs are based on the NCERT/CBSE Class 11 Physics syllabus and are very useful for board exams, improving conceptual clarity and accuracy in problem-solving.
▸ Are these Units and Measurements MCQs important for JEE and NEET?
Yes, this chapter is important for both JEE and NEET. Questions on dimensional analysis, units, and measurement errors are frequently asked in these competitive exams.
▸ Do these MCQs include correct answers and explanations?
Yes, every MCQ is provided with the correct answer along with explanations wherever needed. This helps students understand the reasoning and concepts clearly.
▸ Who should practice Units and Measurements MCQs?
These MCQs are designed for Class 11 students, CBSE/NCERT learners, and aspirants of JEE, NEET, NDA, UPSC, and other competitive exams that include Physics.
▸ Can I practice these Physics MCQs online for free?
Yes, all Units and Measurements MCQs on GK Aim are available online for free. They can be practiced anytime using desktop, tablet, or mobile.
▸ Are these MCQs helpful for quick revision before exams?
Yes, solving these MCQs regularly helps with quick revision, strengthens memory recall, and improves exam performance by enhancing speed and accuracy.
▸ Do these MCQs cover both basic and advanced concepts?
Yes, the MCQs range from basic factual questions to advanced application-based problems, covering significant figures, dimensional equations, and error analysis.
▸ Why are the 398 MCQs divided into 4 parts?
The MCQs are divided into 4 sets to make practice more organized and manageable, allowing students to learn step by step without feeling overloaded.
▸ Can teachers and coaching institutes use these MCQs?
Yes, teachers and coaching centers can use these MCQs as ready-made assignments, quizzes, and practice material for students preparing for board and entrance exams.
▸ Are these MCQs mobile-friendly?
Yes, the Units and Measurements MCQs pages are fully optimized for smartphones and tablets, so students can study anytime, anywhere.
▸ Can I download or save Units and Measurements MCQs for offline study?
Yes, you can download these Units and Measurements MCQs in PDF format for offline study. Please visit our website shop.gkaim.com