full syllabus test-1

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Standard XII : Multiple Choice Questions – TEST : Semester III (Full Syllabus): Ravi Agarwal Date: 16 September, 2014 Name: _____________________________________ Time allotted: 2 hr. 30 min. Maximum marks: 100 THIS QUESTION PAPER CONSISTS OF 64 QUESTIONS. READ INSTRUCTIONS CAREFULLY ON ANSWER BOOK BEFORE SHADING ANSWERS. SECTION A (Question 1 – 40. Each question carries one mark) 1. An electric dipole is placed in a uniform field. The resultant force acting on it________ a. always be zero b. depends on its relative position c. never be zero d. depends on its dipole moment. 2. When an electron and a proton are both placed in an electric field________ a. the electric forces acting on them are equal in magnitude as well as direction. b. only the magnitudes of forces are same c. accelerations produced in them are same d. magnitudes of accelerations produced in them are same. 3. The distance between two point charges 4q and -q is r. A third charge Q is placed at their midpoint. The resultant force acting on —q is zero then Q =_________ a. -q b. q c. -4q d. 4q 4. Two identical metal spheres A and B carry same charge q. When the two spheres are at distance r from each other, the force acting between them is F. Another identical sphere C is first brought in contact with A, then it is touched to sphere B and then separated from it. Now the force acting between A and B at the same distance is________ a. F b. 2F c. d. 5. The electric dipole moment of an HCL atom is . The charges on both atoms are unlike and of same magnitude. Magnitude of this charge is____________.The distance between the charges is 1 a. b. c. d. 6. The line integral of an electric field along the circumference of a circle of radius r, drawn with a point charge Q at the centre will be_____________ a. b. c. d. 7. The area of every plate shown in the Figure is A and the separation between the successive plates is d. What is the capacitance between points a and b? a. b. c. d. 8. A moving electron approaches another electron. What would be the change in the potential energy of this system? a. remains constant b. increases c. decreases d. may increase or decrease 9. A uniform electric field is prevailing in Y-direction in a certain region. The co- ordinates of points A, B and C are (0, 0), (2, 0) and (0, 2) respectively. Which of the following alternatives is true for the potentials at these points? a. b. c. d. 1

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Standard XII : Multiple Choice Questions – TEST : Semester III (Full Syllabus): Ravi Agarwal

Date: 16 September, 2014

Name: _____________________________________ Time allotted: 2 hr. 30 min.Maximum marks: 100

THIS QUESTION PAPER CONSISTS OF 64 QUESTIONS. READ INSTRUCTIONS CAREFULLY ON ANSWER BOOK BEFORE SHADING ANSWERS.

SECTION A(Question 1 – 40. Each question carries one mark)

1. An electric dipole is placed in a uniform field. The resultant force acting on it________a. always be zero b. depends on its relative positionc. never be zero d. depends on its dipole moment.

2. When an electron and a proton are both placed in an electric field________a. the electric forces acting on them are equal in magnitude as well as direction.b. only the magnitudes of forces are same c. accelerations produced in them are samed. magnitudes of accelerations produced in them are same.

3. The distance between two point charges 4q and -q is r. A third charge Q is placed at their midpoint. The resultant force acting on —q is zero then Q =_________a. -q b. q c. -4q d. 4q

4. Two identical metal spheres A and B carry same charge q. When the two spheres are at distance r from each other, the force acting between them is F. Another identical sphere C is first brought in contact with A, then it is touched to sphere B and then separated from it. Now the force acting between A and B at the same distance is________

a. F b. 2F c. d.

5. The electric dipole moment of an HCL atom is . The charges on both atoms are unlike and of

same magnitude. Magnitude of this charge is____________.The distance between the charges is 1

a. b. c. d.

6. The line integral of an electric field along the circumference of a circle of radius r, drawn with a point charge Q at the centre will be_____________

a. b. c. d.

7. The area of every plate shown in the Figure is A and the separation between the successive plates is d. What is the capacitance between points a and b?

a. b. c. d.

8. A moving electron approaches another electron. What would be the change in the potential energy of this system?

a. remains constant b. increases c. decreasesd. may increase or

decrease

9. A uniform electric field is prevailing in Y-direction in a certain region. The co-ordinates of points A, B and C are (0, 0), (2, 0) and (0, 2) respectively. Which of the following alternatives is true for the potentials at these points?a. b. c. d.

10. A parallel plate capacitor is charged with a battery, and then separated from it. Now if the distance between its two plates is increased, what will be the changes in electric charge, potential difference and capacitance respectively?a. remains constant, decreases, decreases b. increases, decreases, decreasesc. remains constant, decreases, increases d. remains constant, increases, decreases

11. A wire has a non-uniform cross-section as shown in figure. A steady current is flowing through it. Then the drift speed of the electrons while going from A to B_________________

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Standard XII : Multiple Choice Questions – TEST : Semester III (Full Syllabus): Ravi Agarwal

a. is constant throughout the wireb.decreases

c. increases d. varies randomly

12.

The cross-sectional area of the plane shown in the figure is equal to 1 . 2A current flows through a conductor. The current density at point P in the conductor will be_____________

a. b. c. d.

13. At what temperature would the resistance of a copper conductor be double its resistance at 0°C? Given for copper =

a. 256.4°C b. 5 12.8°C c. 100°C 256.4 K

d.

14. p and Q are two points on a uniform ring of resistance R. 0 is the centre of the ring. If the part PQ of the ring subtends an angle at the centre 0 of the ring (i.e. ∠POQ = ), the equivalent resistance of the ring between the points P and Q will be___________ [radius of the ring = r and resistance per unit length of the ring = ]

a. b. c. d.

15.

In the circuit shown in figure, what will be the effective resistance between points A and B?

a. b. c. d.

16. In the network shown in figure, the equivalent resistance between points X and Y will_________

a. b. c. d.

17. A particle of mass m has an electric charge q. This particle is accelerated through a potential difference V and then entered normally in a uniform magnetic field B. It performs a circular motion of radius R. The ratio

of its charge to the mass ( )is=__________ [( ) is also called specific charge.]

a. b. c. d.

18. At a place an electric field and a magnetic field are in the downward direction. There an electron moves in the downward direction. Hence this electron_________

a. will bend towards leftb. will bend towards

rightc. will gain velocity d. will lose velocity

19. A long wire carries a steady current. When it is bent in a circular form, the magnetic field at its centre is B. Now if this wire is bent in a circular loop of n turns, what is the magnetic field at its centre?

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Standard XII : Multiple Choice Questions – TEST : Semester III (Full Syllabus): Ravi Agarwal

a. b. c.d.

20.

As shown in the figure two very long straight wires are kept parallel to each other and 2A current is passed through them in the same direction. In this condition the force between them is F. Now if the current in both of them is made 1 A and directions are reversed in both, then the force between them________

a. will be and

attractive

b. will be and repulsivec. will be and

attractive

d. will be and

repulsive.

21. A bar magnet is oscillating in Earth’s magnetic field with periodic time T. If a similar magnet with the same mass and volume has magnetic dipole moment, which is 4 times that of this magnet, then its periodic time will be

a. b. 2T c. T d. 4T

22. Let r be the distance of a point on the axis of a bar magnet from its centre. The magnetic field at r is always proportional to

a. b.

c. d. not necessarily at all points

23. The horizontal and vertical components of magnetic field of Earth are same at some place on the surface of Earth. The magnetic dip angle at this place will bea. 30° b. 45° c. 0° d. 90°

24. Inside a bar magnet, the magnetic field linesa. are not presentb. are parallel to the cross-sectional area of the magnetc. are in the direction from N-pole to S-pole d. are in the direction from S-pole to N-pole

25. A magnetic needle kept on horizontal surface oscillates in Earth’s magnetic field. If the temperature of this needle is raised beyond the Curie temperature of the material of the needle, thena. the periodic time of oscillation will decrease. b. the periodic time of oscillation will increase.c. the periodic time of the oscillation will not change.d. the needle will stop oscillating.

26.

Two similar magnets of magnetic moment are arranged as shown in figure. The magnetic dipole moment of this combination is

a. b. c. d.

27. Depth of a well is 5.5 m and refractive index of water is 1.33. If viewed from the bottom, by how much height would the bottom of the well appear to be shifted up ?a. 5.5 m b. 2.75 m c. 4.13 m d. 1.37 m

3

Standard XII : Multiple Choice Questions – TEST : Semester III (Full Syllabus): Ravi Agarwal28. A point object O is placed midway between on the common axis

of two concave mirrors of equal focal length. If the final image is formed at the position of the object, the separation between two mirrors is______. Focal length of mirrors is f.Hint : A situation is depicted in the figure.Note: Another possible situation for which object and its image coincide is when distance between two mirrors is 4f.

a. f b. 2f c. d.

29. A ray of light is incident normally on the surface of an equilateral prism made up of material with refractive index 1.5. The angle of deviation is______.a. 30° b. 45° c. 60° d. 75°

30. A small linear object of length b is placed on the axis of a concave mirror. The end of the object facing the mirror is at a distance u from the mirror, If f is the focal length of a mirror, the length of the object will be__________ approximately. [Hint Neglect b whenever necessary.]

a. b. c. d.

31. The radii of curvature of both the sides of a convex lens are 15 cm and if the refractive index of the material of the lens is 1.5, then focal length of lens in air is______cma. 10 b. 15 c. 20 d. 30

32. A ray of light experiences minimum deviation by an equilateral prism P. Now two prisms Q and R made of the same material as that of P are arranged as shown in the figure. The ray of light will now experience, (The dimensions of P, Q and R are same.)

a. larger deviation b. no deviationc. same deviation as that due to P d. total internal reflection

33. A defect of vision in which lines in one plane of an object appear in focus while those in another plane are out of focus is called_________________.a. astigmatism b. distortion c. myopia d. hypermetropia

34.

As shown in the figure, thin prisms P1 and P2 are combined to produce dispersion without deviation. For prism P1, angle of prism is 4° and refractive index is 1.54. For prism P2 angIe of prism is 3°. Refractive index of material of P2 is________.

a. 1.72 b. 1.5 c. 2.4 d. 0.58

35. Which of the following statement is not true for a photon ?a. Photon produces pressure b. Photon has energy hf

c. Photon has momentum d. Rest mass of photon is zero

36. Photoelectric effect represents thata. electron has a wave nature b. light has a particle nature c. (1) and (2) both d. none of the above

37. Wavelength and are incident on two identical metal plates and photo electrons are emitted. If

, the maximum kinetic energy of photo electrons is__________.

a. b. c. d.

38. When frequencies f1 and f2 are incident on two identical photo sensitive surfaces, maximum velocities of photo electrons of mass m are v1and v2, hence_______________________________

a. b. c. d.

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Q

P R

Standard XII : Multiple Choice Questions – TEST : Semester III (Full Syllabus): Ravi Agarwal39. Wavelength of an electron having energy 10 keV is_______ .

a. 0.12 b. 1.2 c. 12 d. 120

40. A proton and electron are lying in a box having unpenetrable walls, the ratio of uncertainty in their velocitiesare______________.

a. b. c. d.

SECTION B(Question 41 –55. Each question carries two marks)

41. Two identical conducting spheres carrying difference charges attract each other with a force F when placed in air medium at a distance ‘d’ apart. The spheres are brought into contact and then taken to their original positions. Now the two spheres repel each other with a force whose magnitude is equal to that of the initial attractive force. The ratio between initial charges on the spheres isa. –(3 + ) only b. –3 + only

c. –(3 + ) or (–3 + ) d. +

42.PQR is a right angled triangle in which PQ = 3 m and QR = 4 m and PQR = . The three charges + 15 C, +

12 C and – 20 C are placed respectively on P, Q and R. The force acting on Q is a. 125 N b. 25 N c. Zero d. 35 N

43. Two charge particles 1 and 2 each with charge of 1 C are having the position vectors ( + 2 + 3 ) m and

(4 + 5 + 6 ) m respectively. Then the vector force on particle 2 due to particle 1 is ______ N.

a. ( , , ) b. ( , , ) c. ( , , ) d. 10–9 ( , , )

44. In a given circuit, resistance of each resistor is r. Then equivalent resistance between A and B

a. r b. r

c. r d. r

45. Find the effective resistance between A and B as shown in the figure.

a. r b. r

c. r d.

46.An electron enters a region where electrostatic field is 20 and magnetic field is 5T. If electron passes

undeflected through the region, what will be the velocity of electron?

a. 0.25 b. 2 c. 4 d. 8

47.If a particle of charge 10–12 coulomb moving along the –direction with a velocity 105 experiences a

force of 10–10 newton in –direction due to magnetic field. What is the minimum magnetic field ?

a. 6.25 x 103 tesla in –direction b. 10–15 tesla in –directionc. 6.25 x 10–3 tesla in –direction d. 10 –3 tesla in –direction

48. Two particles X and Y having equal changes, after being accelerated through the same potential difference, enter a region of uniform magnetic field and describe circular path of radius R1 and R2 respectively. What is the ratio of mass of X to that of Y?

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Standard XII : Multiple Choice Questions – TEST : Semester III (Full Syllabus): Ravi Agarwal

a. b. c.

d.

49. At a place horizontal component of earth’s magnetic field is times its vertical component. The magnetic dip angle at the place is _______ radium.

a. 0 b. c. d.

50.Susceptibility of a paramagnetic material at 27C m. At what temperature will it be ?

a. 127C b. 124C c. 327 C d. 30.0C

51. The force between two magnetic poles is F. Now the pole strength of each pole is doubled. Now calculate the new force.

a. 4F b. 2F c. d.

52. A ray of light passes from glass ( = 1.5) to water ( = 1.33). The value of the critical angle of glass is

a. sin –1 b. sin–1 c. sin–1 d. sin–1

53. A plano–convex lens is made of refractive index 1.6. The radius of curvature of the curved surface is 60 cm. The focal length of the lens is _______ cm.a. 50 b. 100 c. – 50 d. – 100

54. The frequency of a light wave in a material is 4 x 1014 H2 and wavelength is 5000 A. The refractive index of material will be a. 1.4 b. 1.5 c. 3.0 d. 1.6

55. A radio transmitter operates at a frequency 880 kHz and a power of 10 kW. The number of photons emitted per second is a. 1.72 x 10 31 b. 1.327 x 1025 c. 1.327 x 1037 d. 1.327 x 1045

SECTION C(Question 56 – 61. Each question carries three mark)

56. A circle having radius a has line charge distribution over its circumference

having linear charge density Calculate the total electric charge

residing on the circumference of the circle.

a. 0 b. c. d.

57. When two dipoles are lined up in opposite direction, the arrangement is known as a quadruple (as shown in the figure). (1) Calculate the electric potential at a point z = z along the axis of the quadruple and

(2) If z >> d, then show that,

a. b.

c. d.

58. A capacitor consists of three parallel plates of equal area A. The distance between them is d1 and d2.

Dielectric material having permittivity is present between the plates. (i) Calculate the capacitance

of such a system. (ii) Express this capacitance in terms of and

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Standard XII : Multiple Choice Questions – TEST : Semester III (Full Syllabus): Ravi Agarwal

a. b. c.

d.

59. As shown in the figure very long conducting wire carrying current is arranged in y direction. Another conducting wire

of length l carrying current is placed on X-axis at a distance from this wire. Find the torque acting on this wire with respect to point O.

a. b.

c. d. zero

60. Calculate the current flowing through the resistor R1 in the given circuit. = 10 , = 20 and

= 30 The potentials of the points 1, 2 and 3 are respectively,

V1 = 10 V. V2 = 6 V andV3 = 5 V. Calculate the potential at the junction is I = ________ and V0 ______

a. 0.4 A, 10 V b. 0.2 A, 8V

c. 0.5 A, 6V d. 0.3 A, 4V

61. As shown in figure, a ray of light in air is incident at on a medium and proceeds ahead in the medium. The refractive index of this medium varied with distance y as

given by, where y is in cm. What is

the angle formed by the ray with the normal at a very large depth?

a. b.

c. d.

SECTION D(Question 62 – 64. Each question carries four mark)

62. As shown in the figure, two concave refracting surfaces of equal radii of curvature (R) and refractive indices (n = 1.5) face each other in air (n = 1.0). A point object (0) is placed midway in between the centre and one of the vertices of the refracting surfaces. What is the distance (in terms of R) between the images of an object due to each refracting surface.

a. 0.40R b. 1.24R

c. 0.114R d. 0.16R

63. A beam of photons of intensity 2.5 W each of energy 11.9 eV is incident on area of the surface having work function 6.4 eV. If 0.63% of incident photons emits photo-electrons, find the number of photons emitted in 1s. Find minimum and maximum energy of these photo electrons.

a. b.

c. d.

64. Two spheres of copper, weighing 1 g each, are kept 1 m apart. The number of electrons in them are 1% less than the number of protons. Find electrical force acting between them. Atomic weight of copper is 63.54 g/mol, atomic no. is 29. Avogadro’s number = NA = 6.023 × 1023 mol-1. a. 439.8 N b. 1.74 10 15 N c. 1.74 10-15 N d. 1.09 10-9 N

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Standard XII : Multiple Choice Questions – TEST : Semester III (Full Syllabus): Ravi Agarwal

INST.:INCOMPLETE CIRCLE/DOUBLE ENTRIES WILL NOT FETCH YOU MARKS

Q response Q response Q response Q response Q response1. 2. 3. 4. 5.

6. 7. 8. 9. 10.

11. 12. 13. 14. 15.

16. 17. 18. 19. 20.

21. 22. 23. 24. 25.

26. 27. 28. 29. 30.

31. 32. 33. 34. 35.

36. 37. 38. 39. 40.

41. 42. 43. 44. 45.

46. 47. 48. 49. 50.

51. 52. 53. 54. 55.

56. 57. 58. 59. 60.

61. 62. 63. 64.

“Prayers, dreams and seeds, all are similar. They have nothing within, but have potential to create everything”

INST.:INCOMPLETE CIRCLE/DOUBLE ENTRIES WILL NOT FETCH YOU MARKS

Q response Q response Q response Q response Q response1. 2. 3. 4. 5.

6. 7. 8. 9. 10.

11. 12. 13. 14. 15.

16. 17. 18. 19. 20.

21. 22. 23. 24. 25.

26. 27. 28. 29. 30.

31. 32. 33. 34. 35.

36. 37. 38. 39. 40.

41. 42. 43. 44. 45.

46. 47. 48. 49. 50.

51. 52. 53. 54. 55.

56. 57. 58. 59. 60.

61. 62. 63. 64.

“Prayers, dreams and seeds, all are similar. They have nothing within, but have potential to create everything”

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Standard XII : Multiple Choice Questions – TEST : Semester III (Full Syllabus): Ravi Agarwal

Q response Q response Q response Q response Q response1. A 2. B 3. A 4. C 5. B6. C 7. B 8. B 9. D 10. D

11. B 12. A 13. A 14. A 15. B16. B 17. A 18. D 19. B 20. A21. A 22. D 23. B 24. D 25. D26. B 27. D 28. B 29. C 30. D31. B 32. C 33. A 34. A 35. A36. B 37. B 38. A 39. A 40. A41. C 42. B 43. C 44. C 45. D

46. C 47. D 48. C 49. C 50. C

51. A 52. A 53. B 54. B 55. C56. C 57. B 58. B 59. B 60. B61. A 62. C 63. B 64. B

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