Oscillations Mock Test – Class 11 Physics

1. A final response curve has almost no visible peak, even though the system is driven through a range of frequencies including its natural frequency. The most likely reason is

2. A spring oscillator has , , and total energy . Its amplitude is

3. In ideal SHM, the speed of the particle is maximum when it is

4. Use the arrangement described below. A point moves anticlockwise with uniform angular speed on a reference circle. Its projection on the horizontal diameter gives SHM with . When the rotating radius makes from the positive horizontal direction, the projection has

5. A statement about resonance says, “Large amplitude occurs because the driving force is always large.” The better correction is that large amplitude at resonance occurs mainly because

6. A displacement equation is used for SHM. At , the velocity is

7. A forced oscillator is first released and then driven by a periodic force. After a long time, the transient free part becomes negligible. The frequency of the steady motion is then mainly

8. A spring of force constant is driven by a periodic force of angular frequency . The mass needed for resonance with this same spring is

9. The elastic potential energy of a spring oscillator displaced by from equilibrium is

10. Assertion: In simple harmonic motion, the acceleration is zero at the mean position.
Reason: In simple harmonic motion, , and the displacement is zero at the mean position.

11. A block of mass is attached to a spring of force constant on a smooth horizontal surface. The angular frequency of small oscillations is

12. Use the graph description below.

The velocity signs at and are respectively

13. If damping in a driven oscillator is increased, the resonance peak generally becomes

14. Use the arrangement described below. A pendulum bob moves along an arc through three marked positions: left extreme , lowest point , and right extreme . For small oscillations, the position usually treated as the mean position is

15. Beats are related to oscillations because they involve

16. Use the graph description below.

The distance travelled by the particle from to is

17. For a spring oscillator, the potential energy at and is

18. A table compares the signs of displacement, velocity, and acceleration for .

The row that needs correction is

19. Assertion: A body can pass through the mean position in SHM with zero acceleration.
Reason: In SHM, acceleration depends on displacement from the mean position.

20. For a SHM particle described by , the signs of , , and at are

21. A mass hangs from a vertical spring of force constant . The static extension of the spring at equilibrium is

22. Consider the following statements about phase in harmonic motion.
I. Phase tells the stage of oscillation.
II. Initial phase depends on the chosen starting instant and representation.
III. Same displacement always means same direction of motion.
Select the valid set.

23. A pendulum clock runs correct at a place where . It is taken to a place where , and its length is not changed. The clock

24. A displacement equation is . The velocity at is

25. In SHM, the magnitude of acceleration is maximum when the body is

26. The time gap corresponding to a phase difference of between two states of the same SHM is

27. Study the table comparing a point in uniform circular motion and its projection on a diameter.

The row that needs correction is

28. A spring-block oscillator has , , and is driven by a periodic force. The driving frequency closest to resonance is

29. The following examples are listed:
I. A pendulum bob swinging through small angles
II. A tuning fork prong moving after being struck
III. The second hand of a clock rotating uniformly
The examples that are oscillatory are

30. A displacement is measured from the mean position. Which force-displacement relation can produce simple harmonic motion of a particle of mass ?

31. A spring oscillator has . At a certain displacement, its kinetic energy is three times its potential energy. The potential energy at that instant is

32. For a set of spring-block systems with the same mass , is plotted against . The graph is a straight line through the origin. Its slope is

33. A spring-block oscillator and a simple pendulum are adjusted to have the same angular frequency. If the pendulum length is and the spring-block mass is , the required spring constant is

34. Assertion: A forced oscillator can have a large amplitude even when the driving force is not very large.
Reason: If the driving frequency is close to the natural frequency, energy can be supplied effectively over many cycles.

35. A displacement function is proposed for SHM. Its second derivative with respect to time is

36. A displacement equation is , where is in and is in . The time period and maximum acceleration magnitude are respectively

37. A mixed oscillator record says: “The amplitude of a spring oscillator is doubled, and its mass is also doubled while the same spring is used.” The correct comparison with the original system is

38. A spring oscillator has , , and total mechanical energy . When the block is at and moving toward the mean position, its velocity is

39. For an oscillator of amplitude , the distance travelled in an arbitrary time interval cannot always be found from only the time interval because

40. Two simple pendulums at the same place have lengths and . For small oscillations, the ratio of their time periods is

41. Study the table for an ideal SHM particle.

The row that gives the proper comparison is

42. A uniform rigid rod of length is suspended from one end and made to oscillate with small angular displacement. Its moment of inertia about the end is , and its centre of mass is at . Its time period is

43. For , the velocity of the oscillator is

44. A pendulum of length is in a lift accelerating upward with acceleration . Its small-oscillation period compared with its period in a stationary lift is

45. A spring oscillator has and amplitude . The maximum elastic potential energy is

46. A vertical spring has static extension when a mass is attached. The mass is then displaced downward from the new equilibrium and given an upward speed . Taking , the amplitude of the resulting motion is approximately

47. The displacement of an oscillator is zero at a certain instant. This does not necessarily mean that

48. A -versus- graph for a simple pendulum has slope . Taking , the value of found from the graph is

49. A block attached to a horizontal spring is pulled slightly and released on a smooth surface. The motion is described as oscillatory because the block

50. A spring oscillator of mass has speed at a certain instant. Its kinetic energy then is