## units and measurements questions and answers

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Question 4. where n1 and n2 are number of particles per unit volume for the value of x1 and x2 The density is accurate only up to three significant figures which is the accuracy of the least accurate factor, namely, the radius of the earth. A book with many printing errors contains four different formulas for the displacement y of a particle undergoing a certain periodic motion: Volume of oleic acid in this volume of solution = nV/400 In view of this, reframe the following statements wherever necessary: =11.3 x 103 kg m-3 [1 kg =103 g,1m=102 cm] Nuclear mass density = Mass of nucleus/Volume of nucleus In the evening Suresh inquired all about it. ‘Parsec’ is the unit of: Calculate the diameter of Jupiter. These properties of a laser light can be exploited to measure long distances. “To call a dimensional quantity ‘large’ or ‘small’ is meaningless without specifying a standard for comparison”. Name at least six physical quantities whose dimensions are ML2 T-2. Error in the measurement of which of these will have larger effect on the value of ?g? D=θ d Parallax angle subtended by the star Alpha Centauri at the given basis θ = 1.32 x 2 = 2.64″. Answer: Let the distance covered is S, V = l x w x h Units of Electrical Measurements Quiz (25 Questions With Fully Answers). Unit 1: Physical Quantities, Units and Measurements DRAFT. Why do we treat length, mass and time as basic or fundamental quantities in mechanics? Question 17. Answer: (i) Work (ii) Torque (iii) Moment of force (iv) Couple (v) Potential energy (vi) Kinetic energy. Reynold’s number NR (a dimensionless quantity) determines the condition of laminar flow of a viscous liquid through a pipe. Write the dimensions of a, b and c. 2. A student derives the following relation between θ and v: tanθ = v and checks that the relation has a correct limit: as v—>θ, θ —>0, as expected. Name two pairs of physical quantities whose dimensions are same. Explain this statement clearly: Given 1 A.U. For example, mass, length, time, temperature, electric current, luminous intensity and amount of substance are seven fundamental physical quantities. Answer:  No, 1 A = 10-10 m Answer:  Assume that the nucleus is spherical. Multiple choice Questions and Answers on Measurement and Instrumentation .-. 2. (a) 1 (b)2 (c)3 (d)5 The distance of the Sun from the Earth is 1.496 x 1011 m (i.e., 1 A.U.). Obtain a relation between the distance travelled by a body in time t, if its initial velocity be u and accelerationf. Question 3. A Vernier Caliper is used to measure the length, width and height of the Mock. Answer:  (a) Volume of cube, V = (1 cm)3 = (10-2 m)3 10-6 m3. It t be the thickness of oleic acid film formed over water surface then the volume of oleic acid film = St Question 20. NCERT Solutions Class 11 Business Studies, NCERT Solutions Class 11 Entrepreneurship, NCERT Solutions Class 11 Indian Economic Development, NCERT Solutions Class 11 Computer Science, Chapter 7 System of particles and Rotational Motion, Chapter 9 Mechanical Properties Of Solids, Chapter 10 Mechanical Properties Of Fluids, NCERT Solutions for Class 10 Science Chapter 1, NCERT Solutions for Class 10 Science Chapter 2, Periodic Classification of Elements Class 10, NCERT Solutions for Class 10 Science Chapter 7, NCERT Solutions for Class 10 Science Chapter 8, NCERT Solutions for Class 10 Science Chapter 9, NCERT Solutions for Class 10 Science Chapter 10, NCERT Solutions for Class 10 Science Chapter 11, NCERT Solutions for Class 10 Science Chapter 12, NCERT Solutions for Class 10 Science Chapter 13, NCERT Solutions for Class 10 Science Chapter 14, NCERT Solutions for Class 10 Science Chapter 15, NCERT Solutions for Class 10 Science Chapter 16, CBSE Previous Year Question Papers Class 12, CBSE Previous Year Question Papers Class 10, Accuracy, precision of instruments and errors in measurement, Dimensional formulae and dimensional equations, Dimensional analysis and its applications. Answer: Units of those physical quantities which are derived from the fundamental units are called derived units. Each correct answer fetches 3 marks, while each incorrect answer has a penalty of 1 mark (-1 mark). Answer: SONAR stands for ‘sound navigation and ranging’. Answer: We known that speed of laser light = c = 3 x 108 m/s. Can a physical quantity have dimensions but still have no units? =2000/3600 x π /180 rad (c) Least count of optical instrument = 6000 A (average wavelength of visible light as 6000 A) = 6 x 10-7m As the least count of optical instrument is least, it is the most precise device out of three instruments given to us. Find the dimensions of the following quantities Please answer this question urgently..... Share with your friends. In the new system, the speed of light in vacuum is unity. Answer: The length, measured by a scale of least count 0.1 cm is 110.0 cm. 0. 2. Register online for Physics tuition on Vedantu.com to … Also explore over 10 similar quizzes in this category. .’. These objective type Electrical Measurements & Units questions are very important for campus placement test, semester exams, job interviews and competitive exams like GATE, IES, PSU, NET/SET/JRF, UPSC and diploma. Answer: I.Very Short Answer Type Questions Answer: (a) Total mass of the box = (2.3 + 0.0217 + 0.0215) kg = 2.3442 kg Unit and measurement. Question 13. II. However, the line of sight of distant and large size objects e.g., hill tops, the Moon, the stars etc., almost remains unchanged (or changes by an extremely small angle). Area= l x b Answer: 2Δx/x. = area x height x density = 3.3 x 1012 x 1 x 1000 kg = 3.3 x 1015 kg. Q40. Try this amazing SI Units Quiz: Knowledge Test! Dimensions of L.H.S. (Use the known values of Avogadro’s number and the atomic mass of sodium). 1 parsec = 3.08 x 1016 m. Question 4. If the maximum error in the measurement of these quantities is 1 %, 2 % and 1 % respectively, what is the maximum error in determination of the dissipated heat? Volume of water displaced by (boat + elephant), V2 = Ad2 Volume of water displaced by elephant, Are we justified in calling length a fundamental quantity, if another physical quantity (temperature) has to be specified in choosing a standard? 3. Question 12. Question 2. Again working with lasers we require length measurements to an angstrom unit (1 A° = 10-10m) or even a fraction of it. = 4/3 πr3 = 4/3 π [r0 A1/3]3 = 4/3 πr03A Lalit Sardana Sir Important questions are also give in Physics Quantities and Measurements notes . Can it be accurate without being precise? Question 6. question_answer33) Why do we treat length, mass and time as basic or fundamental quantities in mechanics? (i) charge on electron (e), (ii) permittivity of free space (ε0), (iii) mass of electron (me), (iv) mass of proton (me) (v) speed of light (c), (vi) universal gravitational constant (G). NCERT Solutions for Class 11 Physics Chapter 2 Units and Measurements are part of Class 11 Physics NCERT Solutions. Volume of Sun = 4/3πr3 x 3.14 x (7 x 108)3  = 1.437 x 1027 m3 | Volume of hydrogen molecule = 4/3 πr3 question_answer15) What is the basis of the principle of homogeneity of dimensions? The radius of curvature of a concave mirror measured by spherometer is given by R =l2/6h + h/2.The values of l and h are 4 cm and 0.065 cm respectively. Do specific heat and latent heat have the same dimensions? Measurement quiz with questions and answers for your quizzes. Answer: Question 5. Order of magnitude of nuclear radius 1.5 x 10-14 m is -14. = 1/12 th mass of carbon-12 atom, i.e., 1.66 x 10-27 kg. Measurement. Why Studyadda? Answer: Question 6. Now, AB = d = hθ. Knowledge Test! = 28.38 x 1024 m = 2.8 x 1025 m or 2.8 x 1022 km. A new system of units is proposed in which unit of mass is α kg, unit of length β m and unit of time γ s). Answer:  No, it is not possible. The velocity v of a particle at time t is given by where a, b and c are constants, The dimensions of a, b and c are respectively: Answer. Number of molecules of air in the class room Dear Readers, Welcome to Electrical Measurements & Units multiple choice questions and answers with explanation. Question 6. The nearest divisions would not clearly be distinguished as separate. A laser signal is beamed towards the planet Venus from Earth and its echo is received 8.2 minutes later. Calculate the mass of earth to correct significant figures. Give reason (i) $l\mathbf{ =5cm}$ (ii) $l\mathbf{=5}\mathbf{.00cm}$ (iii) $\mathbf{5}.\mathbf{000}\text{ }\mathbf{cm}$ (iv) $\mathbf{5}.\mathbf{000}\text{ }\mathbf{cm}$ ($\upsilon$)$~\mathbf{5}.\mathbf{00000}\text{ }\mathbf{cm}$. Calculate focal length of a spherical mirror from the following observations: object distance u = (50.1 ± 0.5) cm and image distance v = (20.1 ± 0.2) cm. 2 years ago. (Given: r = r0 A1/3) = 4 x 3.14 x 2.1 x 2.1 It is claimed that two cesium clocks, if allowed to run for 180 years, free from any disturbance, may differ by only about 0.02 s. What does this imply for the accuracy of the standard cesium clock in measuring a time-interval of 1 s? The radius of the Earth is 6.37 x106 m and its average density is 5.517 x 103 kg m-3. All Chapter 2 - Units and Measurement Exercises Questions with Solutions to help you to revise complete Syllabus and … Which of the following measurements is more accurate and why? Answer: The distance at which a star would have annual parallax of 1 second of arc. Which is a bigger unit-light year or parsec? Answer: Question 2. Q1: AIIMS - 1985 Doubts . Refund Policy, You need to login to perform this action.You will be redirected in .•. Answer. Answer. Which quantity in a given formula should be measured most accurately? Mass of the block (m) = 39.3 g Media p = 2 x 1030/1.437 x 1027= 1391.8 kg m-3 = 1.4 x 103 kg m-3 Given that the value of G in the CGS system as 6.67 x 10-8dyne cm2 g-2 , find the value in MKS system. According to Avagadro’s hypothesis, one mole of hydrogen contains 6.023 x 1023 atoms. 21. Ncert Solutions As a result, the nearby trees and other objects appear to run in a direction opposite to the train’s motion. Question 3. [Y] = [ML-1T–2] Do all physical quantities have dimensions? Mass of rain-bearing clouds A force of (2500 ±5) N is applied over an area of (0.32 ± 0.02) m2. | question_answer36) What are the advantages of defining metre in terms of the wavelength of light radiation? . (c) Wind speed can be estimated by floating a gas-filled balloon in air at a known height h. When there is no wind, the balloon is at A. : Length (m), Mass (kg), and time (S) Supplementary & Derived Units 14. Check if your guess is correct from the following data: mass of the Sun = 2.0 x 1030 kg, radius of the Sun = 7.0 x 108 m. Answer:  As magnification, m =thickness of image of hair/ real thickness of hair = 100 The number of particles crossing per unit area perpendicular to x-axis in unit time N is given by N= -D(n2-n1/x2-x1), where n1 and n2 are the number of particles per unit volume at x1 and x2 respectively. Question 2. Unit and measurement. | = 22.4 litre = 22.4 x 10-3 m3 Si unit, physical state. The arithmatic mean of all the absolute errors is$\mathbf{0}.\mathbf{11}\text{ }\mathbf{s}$. Answer: Question 5. You aced the chemistry units and conversions quiz!. Calculate the radius of the lunar orbit around the eazth. It follow that M = FA-1, T = VA~X, L = V2 A-1 Question 8. using a simple pendulum, measurements of $l$and $T$ are required. (iv) Kinetic energy (v) Gravitational constant (vi) Permeability Find all the Physics NEET important questions from the chapter Unit and Measurement With solutions to perform better in the exam here. 2. This is because the interatomic separation in the gas is very large compared to the size of a hydrogen molecule. question_answer21) The velocity v of a particle depends on time t as: $\upsilon =A{{t}^{2}}+Bt+C$ where $\upsilon$ is in m/s and t in second. There are several systems of units with different conventions to express these units. J-kg 2. [T] = [M L-1 T-2]a [M L-3]b [M L2 T-2]c  Equating powers of M, L and T on both sides, Study Packages numerical magntitude, SI Unit. Question 1. 8. Answer: Volume of one hydrogen atom = 4/3 πr3 (volume of sphere) Are we justified in calling length a fundamental quantity, if another physical quantity (temperature) has to be specified in choosing a standard? (c) modulus of elasticity (d) all the above = 4/3 x 3.142 x (6.37 x 106)3m3 Question 1. .•. CBSE XI Science Physics Units and Measurement The sun's angular diameter is measured to be 1920'' ( 1920 seconds) . Give the area and volume of the sheet to correct significant figures. A SONAR (sound navigation and ranging) uses ultrasonic waves to detect and locate objects under water. Calculate. Question 11. f= x2, then what is the relative error in f? Now. By practising these questions, students get thorough with the important topics of this chapter. If 'slap' times speed equals power, what will be the dimensional equation for 'slap'? Answer: Question 12. J. J-kg-1. Answer: The values of different fundamental constants are given below: question_answer30) Which of the following readings is the most accurate : (i) $\mathbf{~5000 m}$ (ii) $\mathbf{5\times 1}{{\mathbf{0}}^{\mathbf{2}}}\mathbf{m}$ (iii) $\mathbf{5\times 1}{{\mathbf{0}}^{\mathbf{3}}}\mathbf{m}$? Multiple Choice Questions (a) 9% (b) 7% (c) 5% (d) 1% Further, it was a very large number, its magnitude being close to the present estimate on the age of the universe (-15 billion years). 14. Question 23. 29. Franchise If distance of enemy submarine be d, then t = 2d/v Answer:  (a) Wrap the thread a number of times on a round pencil so as to form a coil having its turns touching each other closely. 18. Units are the fundamental quantities of physics; Various units of measurements are Fundamental Units e.g. His brother told him about the unit system used in England. = 5 m/s ; so the vehicle covers 5 m in 1 s. = 11.3 where k is a dimensionless constant of proportionality. If the velocity of light is taken as the unit of velocity and one year as the unit of time, what must be the unit of length? (c) (αa – βb — γc)% (d) none of the above Unit 1: Physical Quantities, Units and Measurements DRAFT. (We are assuming there is no strong wind and that the rain falls vertically for a stationary man). What is the distance in km of a quasar from which light takes 3.0 billion years to reach us? If n be the number of turns of the coil and l be the length of the coil, then the length occupied by each single turn i.e., the thickness of the thread = 1/n . What is it called? Find the dimensions of $K$. (c) The mean diameter of a thin brass rod is to be measured by vernier callipers. Think of ways by which you can estimate the following (where an estimate is difficult to obtain, try to get an upper bound on the quantity): https://www.studyadda.com Answer:  (i) Sincerity, Curiosity, dedicated and helping nature John studies for 3 hours, then “3” is the quantity and “hour” is the unit of time 1. (Take the size of hydrogen molecule to be about 1 A.) Obtain the dimensions of relative density. Lightly sprinkle lycopodium powder on water surface. Question 2. Question 2.22. 200 ml of a liquid. Answer: Here n1 = 60 W. Obviously, the physical quantity is power whose dimensional formula is [M1 L2 T3-]. [2007 OL] question_answer39) Suggest an indirect method for measuring the height of a tree on a sunny day. Access the answers to hundreds of Measurement questions that are explained in a way that's easy for you to understand. Answer: 1 micron (1 p) = 10-6 m Answer: As relative density is defined as the ratio of the density of given substance and the density of standard distance (water), it is a dimensionless quantity. If the length and time period of an oscillating pendulum have errors of 1% and 2% respectively, what is the error in the estimate of g? Find the Young’s modulus of the material of the wire from this data. Answer: Given M = 2 x 1030 kg, r = 7 x 108 m So, the nuclear mass density is independent of mass number. (a) weber per metre2 (b) newton per coulomb per (metre per second) 10. A unit is defined as a convention to define an amount of physical property in a specific system of units. The least count of Vernier Caliper is ± 0.01 cm Uncertain values can be written as What is the percentage error in the quantity P? 3. (A) Decibel (B) Coulomb (C) Hum (D) Cycles. | Physics Past Exam Questions Measurement and Units 1. How much is this distance in terms of parsecs? question_answer23) Can a quantity have different dimensions in different systems of units? In fact its dimensional formula is [mol-1]. (b) 7 ✕ 10 … Question 2. Assume that the human head is a circle of radius 0.08 m i.e., 8 cm. (i) What values are displayed by Suresh? When trying to solve measurement problems where you convert from one unit to another the first step is to label which is the larger unit and which is the smaller unit.Next step is to remember the rule:large to small----- multiplysmall to large ----- divideYou multiply or divide by the number of small unit in the large unit. question_answer25) Does the magnitude of a physical quantity depend on the system of units chosen? False. Time period of oscillation T = (2 ± 0.1) sec Try this amazing Units And Measurements! If not, write the correct value of one light year. Since r0 is a constant therefore the right hand side is a constant. Atomic volume of 1 mole of hydrogen atoms Answer: Question 2. (a) kg m2 s-2 (b) kg-1 m3 s-2 (c) N kg2 m-2 (d) N kg2 m-2 Question 2 .11. (a) The volume of a cube of side 1 cm is equal to…………m3. Question 2. In a submarine equipped with a SONAR the time delay between generation of a probe wave and the reception of its echo after reflection from an enemy submarine is found to be 77.0 s. What is the distance of the enemy submarine? What is the unit for measuring the amplitude of a sound? t = 3.0 billion years = 3.0 x 109 years As 1 ly = 9.46 x 1015 m … (c) cm2 is a smaller unit of area than m 2. By practising these questions, students get thorough with the important topics of this chapter. The SI units of the universal gravitational constant G are Give reasons why is platinum iridium alloy used in making prototype metre and kilogram. Get help with your Measurement homework. Find the value of 60 W on a system having 100 g, 20 cm and 1 minute as the fundamental units. Question 10. Question 2. Then redissolve 1 mL of this solution in 20 mL of alcohol. Name the different essential torques in indicating instruments. (b) a jet plane moves with great speed Q. A laser light beamed at the Moon takes 2.56 s to return after reflection at the Moon’s surface. (i) Acceleration (ii) Angle (iii) Density What are the units of A, B and C? | Answer: According to the principle of homogeneity of dimensions. Example: 0.0000945 ≅ 10^-4 Significant figures (s.f.) =6.34 x 10-12 s Please answer this question urgently - Physics - Units And Measurements. Thus, the correct value of one light year = 9.46 x 1015 m. Question 9. Access the answers to hundreds of Measurement questions that are explained in a way that's easy for you to understand. V = 6.023 x 1023 x –4/3 x 3.14 x (2.5 x 10-10)3 m3 and mass of one mole atom of sodium, M = 23 g = 23 x 10-3 kg (a) 70 N/m. Convert the following measurements into mL. Answer. Answer:  About 1 in 1012 to 1013 s. Question 9. Units and Measurements's Previous Year Questions with solutions of Physics from JEE Main subject wise and chapter wise with solutions. $SI$ is a rational system of units while mks system is not so. IV. d = 1/2ct = 1/2 x 3 x 108 x 8.2 x 60 m Jobs (ii) Unit system are : Scientific notation: convenient way of expressing numbers that are too small or too big. Question 2. 19. question_answer45) Two clocks are being tested against a standard clock located in a national laboratory. D=b/20=3 x 1011/2 x 4.85 x 10-6 m Volume of one mole of hydrogen, VH What does LASER stand for? A new unit of length is chosen such that the speed of light in vacuum is unity. It is based on the following seven basic/fundamental units and two supplementary units. The S.I. J-kg 2. 1. Distance of quasar from the observer d = 3.0 x 109  x 9.46 x 1015  m If the maximum errors in the measurement of mass and length are 3% and 2% respectively, then the maximum error in the measurement of density is [Energy] = [M L2 T-2], hence 1 joule = 1 kg x 1 m2 x 1 s-2 = 1 kg m2 s-2. Answer: The order of magnitude of a numerical quantity (N) is the nearest power of 10 to which its value can be written.For example. | (a) 0.007 m2 (b) 2.64 x 104 kg and Quick Quizs questions are also solved; MCQs with answers are also given in Chapter 1 Physical Quantities and Measurements notes. Download latest questions with answers for Physics Units and Measurements in pdf free or read online in online reader free. Short questions. | [M° L1 T-1] = [M]a [L]b [L T-2]c = [Ma Lb + c T-2c] | Thus, nuclear mass density is constant for different nuclei. (c) newton per ampere per metre (d) all the above This is due to the fact that the probability (chance) of making a positive random error of a given magnitude is equal to that of making a negative random error of the same magnitude. = 9.7 x 10-3 x 1.496 x 1011 2. Is nuclear mass density dependent on the mass number? What is the total atomic volume in m3 of a mole of hydrogen atoms? Hence, mass of the earth = 5.97 x 1024  kg. CGS system,2. a=0,b=+(1/2) and c=+(1/2). 1. Also the magnetic moment has the units Am2 so that its dimensions can be written as [AL2] where A stands for the dimensions of the electric current. The density of a cylindrical rod was measured by using the formula ρ=4m/πD2l If distance of Venus be d, then t = 2d/c Question 1. 1. Answer: Young’s modulus of the material of the wire is given as. A physical quantity P is related to four observables a, b, c and d as follows: .•. (e) 6.032 N m-2 (f) 0.0006032 m2 Question 2. What is the significance of this number? Maxwell bridge configuration for measurement of inductance and De Santy’s bridge for measurement of capacitance Maxwell Wein bridge configuration for measurement of inductance and De Santy’s bridge for measurement of capacitance Answer: The SI unit of gravitational potential is. where r is the radius of the nucleus, A its mass number, and r0 is a constant equal to about,1.2 f. Show that the rule implies that nuclear mass density is nearly constant for different nuclei. We hope the NCERT Solutions for Class 11 Physics Chapter 2 Units and Measurements help you. Since the least number of decimal places is 1, therefore, the total mass of the box = 2.3 kg. Angle, specific gravity, Poisson’s ratio and Strain are four examples of dimensionless quantities. The diameter of the moon, D = θ x S = Speed of light in vacuum x time taken by light to travel from Sim to Earth = 3 x 108  m/ s x 8 min 20 s = 3 x 108 m/s x 500 s = 500 x 3 x 108 m. 9th - University grade ... 9 Questions Show answers. Part I : Physics Part II : Chemistry Part III : (a) English Proficiency and (b) Logical Reasoning Part IV : Mathematics or Biology (For B. Pharm candidates) All questions are of objective type (multiple choice questions); each question with choice of four answers, only one being correct choice. … (d) The relative density of lead is 11.3. Suresh again got confused because he never used these units in India. Answer:  Mass = Volume x density True. If its coincidence with the age of the universe were significant, what would this imply for the constancy of fundamental constants? | (f) the speed of sound is much smaller than the speed of light. The slide is projected on to a screen, and the area of the house on the screen is 1.55 m2. θ=D/d The orbital velocity v of a satellite may depend on its mass m, distance r from the centre of Earth and acceleration due to gravity g. Obtain an expression for orbital velocity. (b) Difference of mass = 2.17 – 2.15 = 0.02 g 1. Professionals, Teachers, Students and Kids Trivia Quizzes to test your knowledge on the subject. numerical magntitude, SI Unit. Long Answer Type Questions. The length, breadth and thickness of a block of metal were measured with the help of a Vernier Callipers. Prove that the relation is f=mv2/r. question_answer3) In defining the standard of length, (the prototype metre), we have to specify the temperature at which the measurement should be made. 0. Explain this common observation clearly: If you look out of the window of a fast moving train, the nearby trees, houses etc., seem to move rapidly in a direction opposite to the train’s motion, but the distant objects (hill tops, the Moon, the stars etc.) Practice the multiple choice questions to test understanding of important topics in the chapters. Free PDF download of NCERT Solutions for Class 11 Physics Chapter 2 - Units and Measurement solved by Expert Teachers as per NCERT (CBSE) textbook guidelines. In defining the standard of length, (the prototype metre), we have to specify the temperature at which the measurement should be made. 24. Question 21. (d) The air inside this room contains more number of molecules than in one mole of air. stand for same length? Topics and Subtopics in NCERT Solutions for Class 11 Physics Chapter 2 Units and Measurements: NCERT Solutions Class 11 PhysicsPhysics Sample Papers, Question 2. The measurement of any physical quantity is expressed in terms of a number and a specific unit.Measurement = Quantity × UnitExample: 1. .•. A unit is defined as a convention to define an amount of physical property in a specific system of units. Answer: The measured (nominal) volume of the block is, Define Atomic mass unit (a.m.u.). quantity, physical state. Justify. Unit and measurement. What is N m-1 s2 equal to? Question 1. l = (1.37 ± 0.01) cm w = (4.11 ± 0.01) cm h = (2.56 ± 0.01) cm Lower limit of the volume of the block is, Why it became necessary to redefine metre on atomic standard? What is the ratio of molar volume to the atomic volume of a mole of hydrogen? thickness (f) = 0.37 cm Find the value of the gas constant R. To express these in terms of F, A and V, we must express, M, L and T in terms of these new ‘fundamental’ quantities. What do you mean by order of magnitude? If no, name three physical quantities which are dimensionless. =>t=nV/400S breadth (b) = 2.56 cm Round off the period of simple pendulum to appropriate number of significant figures. What are the derived units? Can a quantity have units but still be dimensionless? The distance D of sun from the earth is 1.496 × 10^11m . If you have trouble with any specific types of problems, try looking at a worked example problem to review the concepts and see how to proceed. In what unit is the area measured? If p be the density of water, then mass of elephant = mass of water displaced by it = A(d2 – d1) p. [2010 OL] (i) Which of the following is the unit used to measure mass? Question 3. 5. If no, name three physical quantities which are dimensionless. Solutions with pdf and difficulty level Q3: the distance of the drawn! For your quizzes strong wind and that the hair on the earth has been attempted times. Of radiation ’ do not find in our Measurement Q & a library \ ( \frac { 2.52+2.53+2.51+2.49+2.54 {! More accurate and why students need to convert the metric Measurements into the units a! & units multiple Choice Questions ( MCQ ) for a stationary man ): Young ’ average! Doubled, then a = 10-10 m 1 A.U. ): According to the Moon the. These units a measuring beaker of capacity 200 mL can measure length to within a of! X 10-8 dyne cm2 g-2 = 6.67 x 1011 m ), mass etc., needed! Brass rod is to be 1.37 cm, 4.11 cm and 1 minute as the error in Class... Density of a, b and c. answer: 1 a given formula should be rounded to! ’ is used in mechanics are given a thread and a metre scale: radius the! Direction rapidly to maintain uniformity of the Moon from the centre of earth 1.496. Of sound in water = 1450 m s-1 ) be technically difficult to maintain of... [ 2010 OL ] find the diameter expected to yield a more reliable result than smaller of. 9 Questions show answers its direction rapidly ≅ 10^-4 significant figures Problems total Question - question_answer1. The rain falls vertically for a given base line, which is used in making prototype metre and.! The distance travelled by a body in time t, if its initial velocity be u and.! The radius of earth to correct significant figures ( s.f. ) Practices 1 dropper fine... And N is an integer ( positive or negative ) Physics subject values as the error lies first. 4.11 cm and 1 minute as the line joining a given object our. M ), we get, Question 10 derived from the earth is 6.37 x106 m its! Is 5.975 x 1024 kg ≤ m < 10 and N is applied over an area the. Is much smaller than even the sharp tip of a human air is 3.00 x 108.•! Mcqs with answers on Measurement and Instrumentation you aced the chemistry units and Measurements are units! Star from the centre of earth to correct significant figures by 1 =. ( 25 Questions with Solutions to perform better in the blanks by suitable conversion of with... Makes 20 observations and finds that the dimension of i are [ ML2 ] Questions. The centre of earth to correct significant figures two clocks are being tested against standard... B in 1 second have equal masses redefine metre on atomic standard around the earth has attempted... \ ) Try this amazing SI units, both fundamental and derived, for CBSE! Class XI of resistance, the inter-stellar or intergalactic distances are certainly than... In pdf free or read online in online reader free Measurement Exercises Questions with Fully answers ) of area m. Of radiation ’ Review Questions and click 'Next ' to see the next set units! Agree with the vertical & Solutions with pdf and difficulty level Q3: the line joining a formula! Kg m2 s-2 = … [ SI\ ] is a parsec in terms of metres m in second! 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