Tiêu đề 02. UNITS AND MEASUREMENTS (E).pdf ✅

(3) (4) 13. Which of the following numerical values have three significant figures? (1) (2) (3) (4) 14. represents the dimensions of (1) pressure (2) energy (3) power (4) force 15. Dimensions of Gyromagnetic ratio are (1) (2) (3) (4) 16. Poise' is the (1) C.G.S. unit of Surface tension (2) C.G.S. unit of Viscosity (3) M.K.S. unit of Viscosity (4) M.K.S. unit of Surface energy 17. What is the relation between pitch and least count of a screw gauge? (1) (2) (3) (4) 18. The radius of a disc is 1.2 . What is its area with proper number of significant figures? (1) (2) (3) (4) 19. If and denote capacity and resistance, the dimensions of are (1) (2) (3) (4) 20. The physical quantity having the dimensions is (1) Resistance (2) Resistivity (3) Electrical conductivity (4) Electromotive force 21. The dimensions of 'resistance are same as those of_____where is the Planck's constant, is the charge. (1) (2) (3) (4) 22. The density of mercury is . Its value in system will be (1) (2) (3) (4) 23. Which unit is not for length? (1) Light year (2) Parsec (3) Nano (4) Angstrom 24. are the dimensions of (1) Torque (2) Force (3) Angular acceleration (4) Angular momentum 25. If is the inductance, ' ' is current in the cir‐ cuit, has the dimensions of (1) Work (2) Power (3) Pressure (4) Force 26. The dimensional formula for Planck’s constant ( ) is (1) (2) (3) (4) 27. The reliability of a measurement depends on (1) Precision (2) Accuracy (3) Systematic error (4) Random error 28. Unit of emf is (1) joule / sec (2) joule / ampere (3) (4) volt / ampere 29. Which of the following cannot be expressed as dyne ? (1) Pressure (2) Longitudinal stress (3) Longitudinal strain (4) Young's Modulus of Elasticity 30. A physical quantity is described by the rela‐ tion . If the relative errors in the measurement of and respectively, are and , then the relative error in will be (1) (2) (3) (4) 31. The prefix atto means (1) (2) (3) (4) 32. The decrease in percentage error 11.736 cm3 11.7 cm3 0.030 3.033 30.30 0.300 [ML 2T −3] [L 1M0T 1I 1] [L 0M−1T 1I 1] [L1M0T 0I −1] [L−1M0T 1I 1] Pitch = L.C 100 L. C = Pitch 100 Pitch = L. C × 200 L. C = Pitch number of divisions on circular scale cm 4.5 cm2 4.521 cm2 4.52 cm2 4.5216 cm2 C R CR [M0L 0T 1] [M0L 2T −2] [M0L2T −2] [ML0T 0] [M−1L −3T 3A2 ] h e h 2 e 2 h 2 e h e 2 h e 13600 kg m−3 CGS 13.6 g cm−3 1360 g cm−3 136 g cm−3 1.36 g cm−3 [L2M1T −2] L i Li 1 2 2 h ML 2T 2 ML 2T −1 ML −2T −3 ML −2T −2 henry−ampere second cm−2 P P = a 1/2b 2c 3d−4 a, b, c d 2%, 1%, 3% 5% P 8% 12% 32% 25% 10 −21 10 −15 10 −18 10 −12