Q.2 In vertical circular motion, the ratio of kinetic energy of a particle at highest point to that at lowest point is (A) 5 (B) 2 (C) 0.5 (D) 0.

Transcription

1

2 Physics R Q. Fo a gas 0.4, whee R is the univesal gas constant and 'C v ' is mola specific heat at C v constant volume. The gas is made up of molecules which ae (A) Rigid diatomic Monoatomic Non-igid diatomic Polyatomic Q. In vetical cicula motion, the atio of kinetic enegy of a paticle at highest point to that at lowest point is (A) Q. Two wies having same length and mateial ae stetched by same foce. Thei diametes ae in the atio :. The atio of stain enegy pe unit volume fo these two wies (smalle to lage diamete) when stetched is (A) : 9 : 7 : 8 : Q.4 A ing and a disc oll on the hoizontal suface without slipping with same linea velocity. If both have same mass and total kinetic enegy of the ing is 4 J then total kinetic enegy of the disc is (A) J 4 J 5 J 6 J Q.5 When the obseve moves towads the stationay souce with velocity, 'V ', the appaent fequency of emitted note is F. When the obseve moves away fom the souce with velocity 'V ', F V the appaent fequency is F. If V is the velocity of sound in ai and then? F V (A) 4 5

3 Q.6 Wie having tension 5 N poduces six beats pe second when it is tuned with a fok. When tension changes to 56 N, it is tuned with the same fok, the numbe of beats emain unchanged. The fequency of the fok will be (A) 86 Hz 5 Hz 56 Hz 80 Hz Q.7 Assuming the expession fo the pessue exeted by the gas on the walls of the containe, it can be shown that pessue is (A) d d th kinetic enegy pe unit volume of a gas kinetic enegy pe unit volume of a gas kinetic enegy pe unit volume of a gas 4 Kinetic enegy pe unit volume of a gas Q.8 A mass m connected to a hoizontal sping pefoms S.H.M. with amplitude A. While mass m is passing though mean position anothe mass m is placed on it so that both the masses move A togethe with amplitude A. The atio of A is (m m ) (A) m m m m m m m m m m m m

4 Q.9 A paticle moves along a cicle of adius with constant tangential acceleation. If the velocity of the paticle is at the end of second evolution, afte the evolution has stated then the tangential acceleation is (A) Q.0 Two stings A and B of same mateial ae stetched by same tension. The adius of the sting A is double the adius of sting B. Tansvese wave tavels on sting A with speed V and on sting B with speed V B. The atio V V A B is A (A) 4 4 Q. The bob of a simple pendulum pefoms S.H.M. with peiod T in ai and with peiod T in wate. Relation between T and T is (neglect fiction due to wate, density of the mateial of the bob is 9 0 kg / m, density of wate g ) 8 cc (A) T T T T T T T T

5 Q. In a capillay tube of adius R, a staight thin metal wie of adius (R > ) is inseted symmetically and one end of the combination is dipped vetically in wate such that the lowe end of the combination is at same level. The ise of wate in the capillay tube is [T = suface tension of wate, = density of wate, g = gavitational acceleation] T (A) (R ) g T (R ) g T (R ) g (R ) g T Q. When open pipe is closed fom one end then thid ovetone of closed pipe is highe in fequency by 50 Hz than second ovetone of open pipe. The fundamental fequency of open end pipe will be (A) 75 Hz 50 Hz 5 Hz 00 Hz Q.4 A disc of adius R and thickness R 6 has moment of inetia I about an axis passing though its cente and pependicula to its plane. Disc is melted and ecast into a solid sphee. The moment of inetia of a sphee about its diamete is (A) I 5 I 6 I I 64 Q.5 Let a steel ba of length l, beadth b and depth d be loaded at the cente by a load W. Then the sag of bending of beam is (Y = Young s modulus of mateial of steel) (A) Wl bd Y Wl 4bd Y Wl bd Y Wl 4bd Y 4

6 Q.6 Which of the following quantity does NOT change due to damping of oscillations? (A) Angula fequency Time peiod Initial phase Amplitude Q.7 If the end coection of an open pipe is 0.8 cm then the inne adius of that pipe will be (A) cm cm cm 0. cm Q.8 A pogessive wave is epesented by y = sin (5t 4x) cm. On this wave, how fa away ae the two points having phase diffeence of 90? (A) cm cm 4 cm 8 cm 6 Q.9 Two paticles of masses m and 9m ae sepaated by a distance. At a point on the line joining them the gavitational field is zeo. The gavitational potential at that point is (G = Univesal constant of gavitation) (A) 4Gm 8Gm 6Gm Gm 5

7 Q.0 A black ectangula suface of aea A emits enegy E pe second at 7 C. If length and beadth ae educed to becomes (A) 4E 9 7E 9 0E 9 6E 9 d of initial value and tempeatue is aised to 7 C then enegy emitted pe second Q. A liquid dop having suface enegy E is spead into 5 doplets of same size. The final suface enegy of the doplets is (A) E 4E 8E E Q. Let M be the mass and L be the length of a thin unifom od. In fist case, axis of otation is passing though cente and pependicula to the length of the od. In second case axis of otation is passing though one end and pependicula to the length of the od. The atio of adius of gyation in fist case to second case is (A) 4 8 Q. A simple pendulum of length l has maximum angula displacement. The maximum kinetic enegy of the bob of mass m is (g = acceleation due to gavity) (A) mgl ( cos ) mgl ( cos ) mgl ( cos ) mgl (cos ) 6

8 Q.4 Angula speed of hou hand of a clock in degee pe second is (A) Q.5 The value of gavitational acceleation g at a height h above the eath s suface is g 4 then (R = adius of eath) (A) h = R h R h R h R 4 Q.6 In potentiomete expeiment, null point is obtained at a paticula point fo a cell on potentiomete wie x cm long. If the length of the potentiomete wie is inceased without changing the cell, the balancing length will (Diving souce is not changed) (A) incease decease not change becomes zeo Q.7 An ion od is placed paallel to magnetic field of intensity 000 A m. The magnetic flux though the od is Wb and its coss-sectional aea is cm. The magnetic pemeability of the od in Wb is A m (A)

9 Q.8 Altenating cuent of peak value ampee flows though the pimay coil of the tansfome. The coefficient of mutual inductance between pimay and seconday coil is heny. The peak e.m.f. induced in seconday coil is (Fequency of a.c. = 50 Hz) (A) 00 V 00 V V Q.9 An electon of mass m has de-boglie wavelength when acceleated though potential diffeence V. When poton of mass M, is acceleated though potential diffeence 9V, the de-boglie wavelength associated with it will be (Assume that wavelength is detemined at low voltage) (A) M m M m m M m M Q.0 Intefeence finges ae poduced on a sceen by using two light souces of intensities I and 9I. The phase diffeence between the beams is at point P and at point Q on the sceen. The diffeence between the esultant intensities at point P and Q is (A) I 4 I 6 I 8 I Q. Thee paallel plate ai capacitos ae connected in paallel. Each capacito has plate aea 'A' and the sepaation between the plates is d, d and d espectively. The equivalent capacity of combination is ( 0 = absolute pemittivity of fee space) (A) 7 0 A 8d 0 A 8d 0 A 8d 0 7 A 8d 8

10 Q. In an oscillato, fo sustained oscillations, Bakhausen citeion is A equal to (A = voltage gain without feedback, = feedback facto) (A) Zeo Q. Light of wavelength which is less than theshold wavelength is incident on a photosensitive mateial. If incident wavelength is deceased so that emitted photoelectons ae moving with same velocity then stopping potential will (A) incease decease be zeo become exactly half Q.4 A ay of light tavelling though ae medium is incident at vey small angle i on a glass slab and afte efaction its velocity is educed by 0%. The angle of deviation is (A) 8 5 4i 5 Q.5 The maximum fequency of tansmitted adio waves above which the adio waves ae no longe eflected back by ionosphee is (N = maximum electon density of ionosphee, g = acceleation due to gavity) (A) gn gn g N gn Q.6 In Boh s theoy of Hydogen atom, the electon jumps fom highe obit n to lowe obit p. The wavelength will be minimum fo the tansition (A) n = 5 to p = 4 n = 4 to p = n = to p = n = to p = 9

11 Q.7 Two identical paallel plate ai capacitos ae connected in seies to a battey of e.m.f. V. If one of the capacito is completely filled with dielectic mateial of constant K, then potential diffeence of the othe capacito will become K (A) V(K ) V K K KV V K(K ) Q.8 The LC paallel esonant cicuit (A) has a vey high impedance has a vey high cuent acts as esistance of vey low value has zeo impedance Q.9 A galvanomete of esistance 0 is connected to a battey of emf V with 970 esistance in seies. A full scale deflection of 0 divisions is obtained in the galvanomete. To educe the deflection to 0 divisions, the esistance in seies equied is (A) Q.40 Two coheent souces P and Q poduce intefeence at point A on the sceen whee thee is a dak band which is fomed between 4th bight band and 5th bight band. Wavelength of light used is 6000Å. The path diffeence between PA and QA is 4 (A).4 0 cm 4.70 cm cm cm 0

12 Q.4 The schematic symbol of light emitting diode is (LED) Q.4 The amount of wok done in inceasing the voltage acoss the plates of capacito fom 5V to 0V is W. The wok done in inceasing it fom 0V to 5V will be (A) W 0.6 W.5 W.67 W Q.4 Magnetic flux passing though a coil is initially 40 4 Wb. It educes to 0% of its oiginal value in t second. If the e.m.f induced is 0.7 mv then t in second is (A) Q. 44 Resolving powe of telescope inceases when (A) wavelength of light deceases wavelength of light inceases focal length of eye-piece inceases ( D) focal length of eye-piece deceases Q.45 When light of wavelength ' ' is incident on photosensitive suface, the stopping potential is V. When light of wavelength is incident on same suface, the stopping potential is 'V' 6. Theshold wavelength fo the suface is (A) 4 5 Q.46 Fom Bewste s law, except fo polished metallic sufaces, the polaising angle (A) depends on wavelength and is diffeent fo diffeent colous independent of wavelength and is diffeent fo diffeent colous independent of wavelength and is same fo diffeent colous depends on wavelength and is same fo diffeent colous

13 Q.47 Two paticles X and Y having equal chages afte being acceleated though same potential diffeence ente a egion of unifom magnetic field and descibe a cicula paths of adii and espectively. The atio of the mass of X to that of Y is (A) Q.48 When an electon in Hydogen atom evolves in stationay obit, it (A) does not adiate light though its velocity changes does not adiate light and velocity emains unchanged adiates light but its velocity is unchanged adiates light with the change of enegy Q.49 The magnetic field inside a long solenoid having n, tuns pe unit length and caying cuent T when ion coe is kept in it is ( 0 = pemeability of vacuum, = magnetic susceptibility) (A) ni( ) 0 ni 0 ni ( ) 0 ni( ) 0 Q.50 In balanced mete bidge, the esistance of idge wie is 0. / cm. Uknown esistance X is connected in left gap and 6 in ight gap, null point divides the wie in the ation :. Find the cuent dawn the battey of 5 V having negligible esistance. (A) A.5 A A 5 A