## Saturday, 10 January 2015

### BCA Physics Question Bank

PHYSICS – QUESTION BANK – BCA 109

1. What is inertia? Why is Newton’s first low of motion called law of inertia?

2. What is inertia? Discuss its types with one example in each case.

3. State Newton’s second law of motion. Show that it gives the measure of force.

4. Prove that Newton’s second law of motion is the only real law of motion

5. Define the term momentum and impulse. Obtain the relation between impulse and momentum.

6. State Newton’s second law of motion and prove that impulse is equal to the change in momentum.

7. State and explain Newton’s third law of motion. Give two illustrations.

8. State Newton’s third law of motion. Drive the law of conservation of momentum from it.

9. What is difference between mass and weight?

10. How does a weight of man standing in a lift changes, when the lift accelerate (a) upward (b) downward with an acceleration a?

11. What are concurrent forces? Obtain a condition for the equilibrium of three concurrent forces.

12. What is cause of sliding friction?

13. What is limiting friction? State the laws of limiting friction.

14. Show that tanӨ=µ, where Ө is the angle of repose and µ is the coefficient of friction.

15. Define the angle of friction and angle of repose. Show that they both are numerically equal.

16. Friction is necessary evil. Explain. Give two methods to reduce friction.

17. Explain centripetal force and centrifugal force. Why centrifugal force is called a pseudo force?

18. Describe the motion of a car on levelled circular road.

19. Obtain an expression for angle of banking of curved road. Show that it is independent of the mass of the vehicle.

20. Derive the expression for maximum speed of a vehicle on the banked road.

21. Why does a cyclist bend inwards while negotiating a curve? Explain.

22. Explain the term work. Show that work done is equal to dot product of force and displacement.

23. What is meant by positive work, negative work, and zero work? Give one example of each.

24. What are conservative and non-conservative forces? Explain.

25. Define work and power. State their SI units.

26. Define and derive the expression for the kinetic energy.

27. State and prove work-energy theorem.

28. Show that the total mechanical energy of a body falling freely under a gravity is conserved.

29. Derive an expression for the potential energy of stretched spring.

30. What are elastic and inelastic collision? Give examples.

31. Show that in an elastic one dimension collision, the relative velocity of approach is equal to relative velocity of separation after collision.

32. Prove that when two bodies of equal masses undergo elastic collision in one dimension, their velocities are just interchanged.

33. Show that two bodies of equal masses undergoing an oblique collision move at right angle to each other after the collision. (Two dimension)

34. Discuss briefly inelastic collision in one direction.

35. Define coefficient of restitution and discuss for three types of collisions.

36. Obtain the expression for loss of kinetic energy in case of perfectly inelastic collision in one dimension.

37. State and explain lami’s theorem.

38. Discuss the various types of friction.

39. State and explain coulomb’s low of force in electrostatics.

40. Give six properties of electric charge.

41. Write coulomb’s law in vector form. Derive the definition of one coulomb.

42. State the principle of superstition of charges.

43. Derive an expression for electric field intensity at a point at a distance r from a point of electric charge.

44. Explain the properties of electric lines of forces.

45. What is electric flux? Explain.

46. State and prove Gauss’s theorem.

47. State Gauss’s theorem. How coulomb’s law can be derived from it.

48. Using Gauss’s theorem, obtain an expression for the electric field intensity at a point at a distance r from an infinitely long uniformly charged straight wire.

49. Derive an expression for the electric field due to uniformly charged thin spherical shell at a point (a) inside and (b) outside the shell.

50. Find an expression for line integral of electric intensity.

51. What is capacitor? Explain its principle.

52. Derive an expression for the capacitance of a parallel plate capacitor.

53. Derive an expression for the capacitance of parallel plate capacitor with dielectric as the medium between the plates.

54. What is spherical capacitor? Derive expression for its capacitance.

55. Derive an expression for the equivalent capacitance for three capacitors C1, C2 and C3 connected in series.

56. What is resultant capacitance, when a number of capacitors are connected in parallel? Derive the expression for it.

57. What is drift velocity? Establish the relation between drift velocity and electric current.

58. State and explain Ohm’s law.

59. Define resistance of a conductor. What are factors on resistance of conductor depends? Give the corresponding relation.

60. On what factor resistivity of the material depend? Why copper wires are used as connecting wires?

61. Find the total resistance, when the various resistors are connected (i) in series and (ii) in parallel.

62. State Kirchoff’s laws for electric circuits and explain those giving illustrations.

63. Apply Kirchoff’s laws to obtain the condition of balanced Wheatstone bridge.

64. With the help of circuit diagram, explain how a meter bridge (slide wire bridge) can be used to find the unknown resistance of a given wire.

65. Draw a circuit diagram of a meter bridge to compare two resistances. Explain the principle of the experiment and give the formula used.

66. Explain Thomson’s atom model.

67. Explain Rutherford’s experiment on scattering of alpha particles and state the significance of the results.

68. Describe Rutherford’s model for an atom. Give its limitations.

69. Explain the following.
(i) Distance of closest approach.
(ii) Impact parameter.

70. What are the drawbacks of Rutherford’s atom model and how did Bhor remove it.

71. State and explain the postulates of Bhor’s atomic model.

72. What is meant by energy bands in solids? Draw energy band diagrams to illustrate the behavior of        (a) a conductor (b) a pure semiconductor (c) an insulators.

73. What is meant by doping? Explain how it changes the conductivity of the resulting extrinsic semiconductor.

74. Distinguish between intrinsic and extrinsic semiconductors.

75. What is p-n junction diode? Distinguish between forward biasing and reverse biasing in p-n junction.

76. Write a note on LED.

77. Explain the action of n-p-n and p-n-p transistors.

78. What are the advantages of transistors?

79. Write a short note of integrated circuits. Give their uses.