Waves Mock Test – Class 11 Physics

1. In a wave on a rope, the wave speed is . At one instant, a small part of the rope has an upward particle velocity of . The most careful comparison is

2. A string has . The measured slope of a versus graph should be

3. The following pairs are used in a wave description. Identify the pair that is most likely to be confused when distinguishing particle motion from wave motion.

4. The following statements refer to transverse waves on stretched strings.
I. Increasing increases wave speed if is constant.
II. Increasing increases wave speed if is constant.
III. In the same string under the same tension, changing frequency changes wavelength rather than wave speed.
The supported statements are

5. Assertion: Sound cannot be heard across a perfect vacuum.
Reason: Sound is a mechanical wave that needs a material medium to carry pressure disturbances.

6. A learner sees alternate dark and light bands in a spring photograph. The dark bands are regions where coils are crowded, and the light bands are regions where coils are spread out. The photograph most directly represents

7. A wave is described by . A point of constant phase has position at . If , its position at is

8. Two sources produce sound waves of frequencies and . The combined sound travels in air with speed . The beat period and the approximate wavelength corresponding to the average pitch are respectively

9. A sound source moves in a circle around a stationary listener at the centre. At every instant, the source velocity is perpendicular to the line joining source and listener. In the simple line-of-sight Doppler treatment, the observed frequency is

10. Two tuning forks produce beats per second. One fork has frequency . Without any extra information, the other fork may have frequency

11. Use the graph description below.

The vertical distance from the mean line to the highest point represents

12. A transverse wave on a stretched string is given by , where all quantities are in SI units. The string has linear mass density . The tension in the string and the maximum transverse particle speed are respectively

13. A sinusoidal wave travelling toward negative has amplitude , wave number , angular frequency , and zero phase constant. The suitable equation is

14. A stone thrown across a field and a ripple moving across water both involve motion. The motion of the stone is not a wave mainly because

15. The relation shows that

16. A longitudinal wave is travelling through a slinky from left to right. The coils of the slinky move alternately closer together and farther apart. The particle displacement in this wave is mainly

17. A moving ambulance approaches a stationary listener through still air. The listener hears a pitch higher than the pitch heard when the ambulance is at rest. This is an example of

18. The following observations are made for two disturbances on the same stretched string.
I. Disturbance P is produced by one quick jerk.
II. Disturbance Q is produced by regular repeated motion of the hand.
III. Both disturbances travel along the same string under the same tension.
The most suitable conclusion is

19. A source of sound of frequency moves toward a stationary observer with speed . The speed of sound is . The frequency heard by the observer is

20. In a basic comparison of sound speeds, the usual order for many materials is

21. A wave has wavelength . In one representation, this is the distance from one crest to the next crest. In another representation of a sound wave, the same wavelength would be the distance from

22. A compact synthesis problem gives a wave on a string as . The string length is , and both ends are fixed. The frequency of this wave and the harmonic number matching its wavelength are

23. A string has tension and linear mass density . The speed of a transverse wave on it is

24. A final comparison of wave quantities is shown below.

The mismatched row is

25. A liquid has bulk modulus and density . The speed of a longitudinal wave in it is closest to

26. In a closed pipe, the displacement node at the closed end and pressure antinode at the same end occur together because

27. The speed of sound in a gas is at . If the same gas is heated to , the new speed is closest to

28. In an open pipe, end correction is introduced because

29. A standing wave on a string is represented by . The positions of nodes satisfy

30. The wave number of a sinusoidal wave is related to wavelength by

31. A pipe open at both ends vibrates in its fundamental mode. The length of the pipe is related to the wavelength by

32. The following table lists Doppler cases in still air. Identify the row with the suitable frequency trend.

The fully suitable rows are

33. A fixed string vibrates in a mode with three loops between its ends. This mode corresponds to

34. An aircraft travels at in air where the speed of sound is . Its Mach number is

35. A sound source and a listener move with the same speed toward each other in still air. Compared with the emitted frequency, the heard frequency is

36. The spacing between successive similar features in a periodic wave is interpreted using phase. For a transverse displacement wave, the nearest similar feature after a crest is

37. Two identical waves of the same amplitude and frequency travel along the same string in opposite directions. Their superposition can form

38. A sinusoidal wave has wavelength . The wave number is

39. A gas at has sound speed . The same gas is heated so that the sound speed becomes . The final temperature is

40. The quantity that tells how many complete oscillations occur in is

41. Study the table for a string fixed at both ends and identify the mismatched row.

42. Two wave records are compared.
I. Record P shows complete oscillations in .
II. Record Q has time period .
The frequencies of P and Q are respectively

43. A snapshot of a wave on a string is drawn as versus . The distance from one crest to the next crest is , and the vertical distance from the mean line to a crest is . The wavelength and amplitude are

44. A closed resonance tube has first resonance length for a tuning fork. The wavelength of the sound is known to be . The end correction is

45. A source of frequency moves toward a stationary observer at speed . The speed of sound is . The wavelength of sound in front of the moving source is

46. A graph of versus at fixed shows successive crests separated by . A graph of versus at fixed shows successive maxima separated by . The wave speed is

47. The following statements about waves are given.
I. Wave speed and particle speed are always the same.
II. A closed pipe supports only odd harmonics in the ideal model.
III. In a graph at fixed , the time between successive maxima gives .
IV. Beats per second equal the sum of the two frequencies.
The supported statements are

48. In the equation , increasing while keeping , , and unchanged will

49. A phase difference of corresponds to what path difference in terms of wavelength?

50. Two tuning forks of frequencies and are sounded together. During the beat formation, the loudness becomes maximum