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1.	When light of wavelength l less than threshold wavelength l₀ is incident on a metal surface, the emitted electrons :
	(1) will have kinetic energy proportional to the intensity of the incident light. (2) will have kinetic energy that depends of the wavelength of the incident light. (3) are called photons. (4) will have no kinetic energy.




2.	Light of frequency 8 x 10¹⁵ Hz is incident on a substance of photoelectric work function 6.125 eV. Calculate the maximum kinetic energy of the emitted photoelectrons.
	(1) 17 eV (2) 37 eV (3) 27.0 eV (4) 22.7 eV




3.	When a point source of light is 1 m. away from a photoelectric cell, the photoelectric current is found to be I mA. If the same source be placed at 3 m. from the same photo electric cell, the photoelectric current will be.
	(1) 1/9 mA (2) 1/3 mA (3) 3 ImA (4) 9 ImA

4.	A p-type semiconductor is germanium doped with :
	(1) Gallium (2) Any one of these (3) Aluminum (4) Boron

5.	In the normal operation of a transistor:
	(1) both (3) and (4) are true (2) neither (3) Nor (4) in true (3) the collector -base junction is forward biased (4) the emitter-base junction is reverse biased.




6.	The concept of quantum nature of light has emerged in an attempt to explain:
	(1) black -body radiation (2) photoelectric effect (3) polarisation of light (4) interference and diffraction


7.	Two concentric coplanar circular loops of radii 7 cm and 10 cm carry currents such that the net magnetic induction at their common centre is zero, If the current in the outer loop is 7 A clockwise, the current in the inner loop must be:
	(1) 1 A clockwise (2) 4.9 A anticlockwise (3) 10 A clockwise (4) 49 A anticlockwise


8.	A man is sitting in a room with his back against a wall. An electron beam moving horizontally from the back wall to the front wall is deflected towards his right. What is the direction of the uniform magnetic field in the room?
	(1) vertically downwards (2) to his right (3) vertically upwards (4) to his left.


9.	A zero to 20 mA ammeter has a resistance of 20 ohm, To convert this into a voltmeter of range zero to 10 V, the resistance to be connected in series with it is:
	(1) 480 ohm (2) 580 ohm (3) 280 ohm (4) 380 ohm


10.	A copper ring is moved quickly towards the south pole of a powerful stationary bar magnet.
	As result:
	(1) a current flows through the copper ring (2) a current flows in the magnet (3) the copper ring will get magnetised (4) the copper ring will get attracted




11.	Let L denote the self-inductance of a coil which is in series with a capacitor of capacitance C Which of the following has the unit second ?
	(1) CL (2) L²C² (3) �LC (4) C/L


12.	Let Q denote the charge on the plates of a capacitor of capacitance C. The dimensional formula for Q²/C is :
	(1) LMT² (2) L²M²T (3) L²M²T² (4) L²MT^-2


13.	A body moving along a straight line with a uniform acceleration covers 20 cm. In one second and 30 cm. in the very next one second. The body has an acceleration of:
	(1) 10 cm/s² (2) 5 cm/s² (3) 30 cm/s² (4) 20 cm/s²


14.	The centripetal force required to keep a body in uniform circular motion depends on its:
	(1) radius of the path (2) all these (3) mass only (4) speed only


15.	It is easier to life a heavy stone under water than in air, because:
	(1) of the resultant up thrust of water (2) none of these reasons (3) acceleration due to gravity is lesser in water. (4) mass decreases in water.




16.	A candle frame produces a ...... emission spectrum.
	(1) continuous (2) none of these (3) line (4) band


17.	The activity of a radioactive sample can be increased by:
	(1) applying intense electric field (2) no method (3) heating it. (4) applying pressure on it.


18.	A sample of a radioactive substance contains 2,828 atoms. If its half-life is two days, how many atoms will be left intact in the sample after one day?
	(1) 2,000 (2) 1,000 (3) 1,414 (4) 707


19.	I a.m.u. cannot be expressed in:
	(1) joule (2) Newton (3) electron volt (4) kilo-watt hour.


20.	A is the mass number of an element. The volume of the nucleus of an atom of this element is proportional to:
	(1) A (2) A^1/3 (3) A³ (4) A²

21.	A liquid in motion possesses:
	(1) only pressure energy due to its pressure (2) all these forms of energies (3) only kinetic energy due to its motion (4) only potential energy due to its position.




22.	A Carnot engine takes heat from a reservoir at 627⁰C and rejects heat to a sink at 27⁰C. Calculate its efficiency.
	(1) 200/209 (2) 3/5 (3) 1/3` (4) 2/3

23.	Two concurrent equal forces of magnitude 5 N each act at an angle 120 deg. The magnitude of their resultant is:
	(1) 15 N (2) 5�3 N (3) 5 N (4) 10 N

24.	A sonometer wire under a tension T emits a note of fundamental frequency 200 Hz. The tension is increased by 3T. The frequency of the fundamental note emitted will be:
	(1) 100 Hz (2) 200/�3 Hz (3) �3 x 200 Hz (4) 400 Hz

25.	A train is approaching a stationary listener on a railway platform and the train whistles. The apparent frequency of the whistle heard by the listener will:
	(1) be more than the frequency of the whistle (2) depend on the temperature of the atmosphere (3) be the same as the frequency of the whistle. (4) be less than the frequency of the whistle.




26.	An aero plane having a wing span of 35 m. flies due north at a speed of 90 m/s. Given B, =4 x10^-5T, the p.d. between the tips of the wings will be:
	(1) 1.26 V (2) 0.013 v (3) 0.126 V (4) 12.6 V

27.	In an L,C, R series circuit, under conditions of resonance the current:
	(1) is in phase with the voltage (2) leads the voltage by 45⁰ (3) leads the voltage by 90⁰ (4) lags behind the voltage by 90⁰


28.	The electron in the innermost orbit of an atom has ....... velocity.
	(1) mean (2) zero (3) highest (4) lowest.

29.	Given the wavelength of the first member of the Lyman series in 1215 A. U., find the wavelength of the H-beta H_β line:
	(1) 3,645 A.U (2) 6,075 A.U (3) 4,860 A.U (4) 2,430 A.U

30.	The number of photons required to supply a definite amount of energy:
	(1) varies inversely as wavelength (2) is independent of wavelength and frequency (3) varies directly as frequency (4) varies directly as wavelength.


31.	The susceptibility of a ferromagnetic material is K at 27 deg. C. At what temperature will be susceptibility be 0.5 K?
	(1) 600⁰C (2) 237⁰C (3) 54⁰C (4) 327⁰C

32.	A certain charge Q is to be divided into the parts q and (Q -q), What is the relation between Q and q if the two parts placed at a given distance apart to have a maximum force of repulsion?
	(1) Q = 3q (2) Q = 1.5q (3) Q = 2q (4) Q = 4q

33.	Check the only true statement below: A deuteron and a triton are placed is the same electric field.
	(1) Force on deuteron is thrice the force on triton. (2) Acceleration of triton is 1.5 times that of deuteron (3) Force on triton is twice the force on deuteron. (4) Acceleration of deuteron is 1.5 times that of triton.




34.	A particle of charge Q and mass m travels through a potential difference V from rest. The final momentum of the particle is:
	(1) mV/Q (2) 2Q�mV (3) �2mQV (4) �2QV/m

35.	Three point charges of 0.67nC, 0.97 nC and -0.35 nC are placed at the corners A, B and C of square ABCD, Find what charge must be placed at the corner D of the square so that the net potential at the centre of the square is zero.
	(1) -1.99 nC (2) -1.29 nC (3) 1.29 nC (4) 1.99 nC

36.	A ray of light is incident in glass at 3I⁰42^' on a glass-water boundary. If the angle of deviation of the ray is 4.5 deg., the angle of refraction in water will be:
	(1) 26⁰92^' (2) 36⁰12^' (3) 27⁰12^' (4) 35⁰92^'

37.	The vertical shift produced due to normal refraction:
	(1) decreases with increase of depth (2) does not depend on these factors (3) increases with increase of refractive index (4) decreases with increase of refractive index.



38.	A ray of light in glass of refractive index 1.5 is incident at an angle of 50⁰ on glass-air boundary. Calculate the angle of deviation of the ray.
	(1) 80 deg. (2) can't be found out (3) 96 deg. (4) 48⁰36'


39.	When light is refracted through a prism, maximum deviation occurs when:
	(1) either of the above happens (2) neither of the above happens (3) the ray is incident grazing the first face. (4) the ray emerges out grazing its second face.



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40.	A ray of monochromatic light is a incident at an angle 49⁰ on the first face of an equilateral prism placed in the minimum deviation position, Find the angle between the emergent and incident rays:
	(1) 11⁰ (2) 22⁰ (3) 38⁰ (4) 19⁰

41.	Charge of + 10 nC and -10nC are placed at A and B.P and Q are two points lying on the perpendicular bisector of the line AB. Work done in taking a charge of 5 nC from P and Q
	(1) depends only on the charge shifted (2) is zero (3) depends only on the distance PQ (4) depends only on the distance AB.




42.	A conducting sphere of radius 10 cm. is charged with 10 micro C. Another uncharged sphere of radius 20 cm. is allowed to touch it for enough time. After the two are separated, the surface density of charge on the two spheres will be in the radio:
	(1) 2 : 1 (2) 1 : 1 (3) 4 : 1 (4) 3 : 1

43.	n identical mercury droplets charged to the same potential V coalesce to form a single bigger drop. The potential of the new drop will be:
	(1) nV (2) V/n (3) n^2/3V (4) nV³

44.	Two capacitors of capacitances C₁= 2 micro F and C₂= 3 micro F are connected in series across 10 V. The potential difference across the plane of the capacitor C₁ will be:
	(1) 2 V (2) 3 V (3) 6 V (4) 4 V

45.	When two charged conductors share their charges due to contact, there will be ..... of energy.
	(1) no change (2) no conversion (3) a gain (4) a loss.

46.	A cell of e.m.f. 1.5 V and internal resistance 2 ohm is connected to two resistors of 5 ohm and 8 ohm in series. The potential difference across the 5 ohm resistor will be:
	(1) 1 V (2) 0.33 V (3) 3.3 V (4) 0.5 V

47.	Seven identical cells whether connected in series or in parallel send the same current through an external resistance 2.1 ohm. The internal resistance of each cell must be:
	(1) 4.9 ohm (2) 2.1 ohm (3) 0.3 ohm (4) 14.7 ohm.

48.	At 1000⁰C the resistance of a wire is found to be four times its resistance at zero deg. C. Calculate the temperature coefficient of resistance of the material of the wire:
	(1) 0.002/⁰C (2) 0.001/⁰C (3) 0.004/⁰C (4) 0.003/⁰C

49.	What is the potential difference between X and Y in the diagram given here ?

	(1) 3 V (2) 1 V (3) 9 V (4) 6 V

50.	In the circuit given here, the galvanometer G reads zero. If the internal resistance of each battery is zero, what must be the resistance of the wire marked R?

	(1) 2.5 Ω (2) 7.5 Ω (3) 5 Ω (4) 10 Ω

51.	The refractive index of glass is 1.67 for violet light, 1.65 for yellow light and 1.63 for red light. The dispersive power of glass is:
	(1) 0.031 (2) 1.06 (3) 0.0615 (4) 0.024.

52.	A slide projector forms an image 3.5 m, high of an object 35 mm, in height. The illumination of the object and the image will be in the ratio:
	(1) 10³:1 (2) 10⁴:1 (3) 1:10⁴ (4) 1:10²

53.	The time of exposure of a photographic print is:
	(1) directly proportional to the square of the illumination. (2) inversely proportional to the square root of the illumination. (3) directly proportional to the illumination. (4) inversely proportional to the illumination.




54.	Fringe width observed in the young's double slit experiment is β. If the frequency of the source is doubled. the fringe width will:
	(1) become 2β (2) become 3β/2 (3) remain as β (4) become β/2

55.	Diffraction effects are more pronounced or easier to notice in the case of sound waves than in the case of light waves, because:
	(1) sound travels faster than light. (2) sound waves have a smaller wavelength (3) sound waves are of longer wave length. (4) sound waves are longitudinal.




56.	Three resistors of 1 ohm, 2 ohm and 3 ohm are connected in parallel. If a current of 11 A enters this combination, the current through each resistor is respectively:
	(1) 6A, 3A, 2A (2) 11/6 A, 11/3 A, 11/2 A (3) 3A, 2A, 1A (4) 6A, 4A, 2A.


57.	A 30 V, 90 W lamp is to be operated on a 120 V.D.C line. For proper glow, a resistor of ...... should be connected in series with the lamp.
	(1) 30 Ω (2) 40 Ω (3) 10 Ω (4) 20 Ω

58.	In the circuit given here, the voltmeter V reads 3 volt, Calculate the resistance of the voltmeter:

	(1) 1,200 Ω (2) 1,000 Ω (3) 1,600 Ω (4) 1,400 Ω

59.	Material used in the construction of a standard resistance must have ......... temperature coefficient of resistance.
	(1) almost zero (2) a very high (3) a positive (4) a negative.

60.	A battery consists of a variable number (n) of identical cells each having an internal resistance r connected in series. The terminals of the battery are short-circuited. A graph of current (I) in the circuit verses number of cells (n) will be as shown in..........

	(1) figure (c) (2) figure (d) (3) figure (a) (4) figure (b)

61.	A bar magnet is placed with its axis parallel to the arm of a deflection magnetometer arranged for tan A position and the deflection recorded in the compass box is 60 deg. What will be the deflection produced, if the bar magnet is rotated by 90⁰?
	(1) 45⁰ (2) 60⁰ (3) zero deg. (4). 30⁰

62.	At a null point, the period of vibration of a bar magnet is:
	(1) infinity (2) none of these (3) zero (4) 1 sec.

63.	In a dip circle, the dip needle reads 90⁰- 90⁰ when the plane of rotation of the dip needle is?
	(1) vertical (2) perpendicular to the magnetic meridian (3) horizontal (4) in the magnetic meredian.




64.	At a place, the horizontal and vertical components of the earth's field are 4.5 x 10^-5T and 6 x 10^-5 T. The total field of the earth at the place is .......x 10^-5 T.
	(1) 9 (2) 10.5 (3) 1.5 (4) 7.5


65.	The ratio of the magnetic induction to the intensity of the magnetizing field is called:

	(1) susceptibility (2) retentivity (3) relative permeability (4) absolute permeability


66.	A parallel beam of light in air is incident on a glass sphere of refractive index 1.5 and diameter 20 cm, parallel to its horizontal diameter. The rays converge to a point at a distance of ....... from the centre of the sphere.
	(1) 10 cm (2) 15cm (3) 20 (4) 5 cm

67.	The projection lens of a projector has a focal length 5 cm. It is desired to get an image with a magnification 30. The distance of the screen from the lens must be
	(1) 1.55 m (2) 5 cm (3) 0.3 cm (4) 3m.

68.	A convex lens placed at a distance of 0.1.m. from the on object produces a magnified image on the screen. Without disturbing the object or the screen. the lens is moved by 0.2 m. towards the screen and a diminished image is formed on the screen. The focal length of the lens must be:
	(1) 15 cm (2) 20 cm (3) 7.5 cm (4) 10 cm.

69.	A convex lens and a concave lens of unknown powers are given to you. The lens of higher power is:
	(1) determined by the nature of the image formed by the lens combination. (2) determined by the colour of light used. (3) always convex. (4) always concave.




70.	Whenever composite light is not refracted by the surface of an optical medium, light will:
	(1) get deviated as well as dispersed. (2) neither get deviated nor dispersed. (3) get dispersed but not deviated. (4) get deviated but not dispersed.