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-24/102021, , AGHMODE PHYSICS ACADE Ve ies, , Exam Name :-Units and measurement Mark :- 100, , , , , , 1, 1f f = x3, then the relative error in F is, , 2Ax (ax)?, (a) x (b) x, ax (a) (Ax)?, (c) x, 2. If error in radius is 3%, what is error in volume of sphere?, (a) 3% (b) 27%, (c) 9% (d) 6%, 3. Find the dimensions of electric permittivity, (a) [@M“LT4] (b) M411?), (c) (AM“*L-*T4] (d) [APMeL-* 74], 4. The number of significant figures in all the giveit numbers 25.12, 2009, 4.156 and 1.217 x 107* is, (a) I (b)2, (c)3 (dy4, 5. a aThe dimensions of 5 in the equation P=e where P is pressure, is distance and € is time, are, (a) [M?LT~3] (b) IMT~2], (c) LT-*) (d) [MIF T-*], 6. In the equation ¥ = @ sin ( @t + kX ) the dimensional formula of @ is, (a) [M°L°T-*] (b) M°LT-*], (c) [ML°T°} (a) [M°L™ T°], , 7.1f F =6nn*r°v® | Where F = viscous force 9 = coefficient of viscosity "= radius of spherical body ¥ =, terminal velocity of the body. Find the values of @,B and ¢ ., , (a)@=1b=2,c=1 (bh)a=1b=1Le=1, (c)@=2,b=1,c=1 (d)@=2,b=1,c=2, >, 8. Tf the velocity v(is cms) of a particle is given in terms of t (in second) by the relation v=at Bae then,, , the dimensions of @,D and ¢ we abe, , (a) fT) fr?) (1) ff) fr], (c) LT?) [LT] wu @2T7] ft} fT, > Given, Farce ™ density? B* What are the dimensions of % B?, (a) (Mi? T~], [ML-¥] (by M7L*T-?], [M¥5L~], (c) IM7L-*7-4], [M¥7L~] (d) M775], [ML], 10. If L = 2.331 cm,B = 2.1 cm, then L + B is equal wo, (a) 4.431 cm (b) 4.43 cm, (oc) 44cm (d)4 cm, , 11. The magnetic force on a point moving charge is F = q(V XB) . Here, 7 = electric charge V= velocity of
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B= magnetic field The dimensions of 5B, oe ap (b) [MLT-74-4], (c) MT-*a*] (d) None of these, , FLL, a To determine the Young s modulus of a wire, the formula is r=; *an; where b= length, A = area of, , cross-section of the wire, AL= change in length of the wire when stretched with a force F . The, conversion factor to change it from CGS to MKS system is, (a)l (b) 10, (c) 0.1 (d) 0.01, 13. A physical quantity is given by X = M*L°T® . The percentage error in measurement of M,Z and T are @B, and ¥ respectively. The maximum percentage error in the quantity % is, , (a) aa + DB + cy (b) aa + BB — cy, pally b a= (d) None of these, (a BY, , 14. If force (F) , velocity (V) and time (7) are taken as fundamental units, then the dimensions of mass are, (2014), (a) (FvT~*) (b) Fvr-*], (c) Fur] (a) FV-*7], 15. 7, A physical quantity A is related to four observations @8,€ and @ as follows, — eva . The percentage error, of measurement in @,B,¢€ and @ are 196,3%,2% and 2% respectively. What is the percentage error in the, quantity A, (a) 12% (b) 7%, (c) 5% (d) 14%, , = a, The position of a particle at time * is given by the equation x@) = - G—e*),¥0 = constant and A > 0., Dimensions of % M4 A respectively are, , 16., , (a) [M°LT®] and [M°L°T-?] (b) [M°LT™] and [M°LT~], (c) [M°LT~*) and [M°L°T] (d) [M°LT~) and [M°L°T-*], af, In the gas equation (e +3) WV —b)=RT, the dimensions of @ are, (a) [ML°T~7] (b) [M419 T-4], (c) MLFT~] (¢) M“LT?], 18, [ML?L~* hire dimensions of, (a) Force (b) Moment of force, (c) Momentum (d) Power, 19. 2.10+2.666, (a) 4.677 (b) 4.76 cm, (c) 4.7em (d) 4.7666cm, , 20. In a system of units if force (F) , acceleration (A) , and time (7) are taken as fundamental units then the, dimensional formula of energy is, , (a) FAT (b) FAT?, (c) F2AT (d) FAT, 21. 1f = @—B, then the maximum percentage error in the measurement of X will be, ‘da + ‘a Ab, wl —_e wae ~p) x 100%, Ae ae) x 100% on -) x 100%, (c)\a-a a (@d)\a-a a, , 22. Consider a new system of units in which € (speed of light in vacuum), @ (Planck s constant) and G
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(gravitational constant) are taken as fundamental units. Which of the following would correctly represent, mass in this new system?, , he Ge, , (a) 6 (b) &, , hG (d) VAGe, or ©, , 23. The velocity of a particle ¥ at an instant € is given by ¥ = at + bt? the dimension of B is, , (a) 1] (b) LT~*], (c) LT-7] (d) LT], 24. Given ™ = 3.14 , the value of 1? with duc regard for significant figures is, (a) 9.86 (b) 9.859, (c) 9.8596 (d) 9.85960, , 25. The period of oscillation of a simple pendulum in the experiment is recorded as 2.63 s, 2.56 s, 2.42 s, 2.71 s, and 2.80 s respectively. The average absolute error is, (a) O.1s (b) O.11s, (c) 0.01 s (d) 1.0s
