Waves Mock Test – Class 11 Physics

1. For a string fixed at both ends, the allowed wavelengths are

2. A displacement-position graph of a transverse wave shows a crest-to-crest separation of . A pressure-position graph of a longitudinal sound wave shows a compression-to-compression separation of . The two separations represent

3. A wave travelling from one medium into another has its frequency unchanged but its wavelength changes from to . If the original speed was , the new speed is

4. A wave equation is written as in SI units. The maximum particle speed and wave speed are respectively

5. In a longitudinal wave travelling along the -axis, a particle of the medium is displaced first toward and then toward . This description means that the particle

6. A sound wave in a fluid has bulk modulus and density . A source produces frequency in this fluid. The wavelength is closest to

7. The following statements describe sound characteristics.
I. Increasing frequency generally increases perceived pitch.
II. Increasing amplitude can increase loudness through greater intensity.
III. Quality depends only on wave speed in air and not on waveform.
The supported statements are

8. A wave travelling along a string is photographed at two instants separated by . A particular crest is at in the first photograph and at in the second. The wave speed and direction are

9. A graph is drawn for a particle of a medium at fixed . The graph is useful for finding

10. A wave on a string is given by . The same string is fixed at both ends and has length . The harmonic number that matches this wavelength is

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

12. Two statements about the Doppler effect for sound are given.
I. Motion along the line joining source and observer affects the observed frequency.
II. Motion perpendicular to the line joining source and observer gives the same first-level Doppler shift as direct approach.
III. The simple school-level formula assumes sound speed measured in the medium frame.
The supported statements are

13. In a resonance tube closed by water, the first two resonance lengths are and . If end correction is present but unchanged, the difference equals

14. The pair that represents a wave quantity and its usual SI unit is

15. Two tuning forks of frequencies and are sounded together. The number of beats heard per second is

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

17. In a progressive wave , the particle velocity of the medium is obtained by

18. A travelling wave enters a second part of a string where the wave speed becomes smaller, while the source frequency remains unchanged. The wavelength in the second part

19. A source moves through air at Mach . If the speed of sound is , the source speed and the value of for its Mach cone are respectively

20. A claim says: “If a wave travels from left to right, every particle of the medium must also move from left to right permanently.” The best correction is that

21. The following situation describes a transverse wave on a string.

What can be said about the wave and that portion of the string?

22. A source moving at speed emits sound of frequency . A stationary observer in front of the source hears . If is much smaller than , the fractional increase in frequency is approximately

23. A wave transfers energy and momentum through a medium, but this does not mean that

24. A proposed relation for wave speed on a string is . The best criticism is that

25. 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

26. A string of length has total mass . Its linear mass density is

27. Two identical upward pulses meet on a string. At the instant of complete overlap, the displacement of the string is

28. A crest in a transverse wave represents

29. A closed pipe of length contains air in which the speed of sound is . The frequency of its third allowed mode is

30. A gas and a solid are both able to transmit sound. The main reason both can do so is that both

31. The frequency of the -th harmonic of a string fixed at both ends is

32. A string fixed at both ends is vibrating in the fifth harmonic. Its length is , and the wave speed is . The frequency is

33. A wave of frequency travels from string P, where its speed is , into string Q, where its speed is . The wavelength in string Q is

34. Two waves travel toward the east through different media. In wave I, particles move north-south. In wave II, particles move east-west. The correct classification is

35. The phase of a sinusoidal wave at a point changes by in . The angular frequency is

36. A sinusoidal wave is written as , with SI units. At and , the particle velocity is

37. Two records are made for the same travelling wave.
Record P: versus at a fixed .
Record Q: versus at a fixed .
The quantities most directly read from P and Q are respectively

38. In the phase expression , the term is dimensionless because

39. A string fixed at both ends has length , and the wave speed on it is . Its fundamental frequency is

40. A statement says, “Sound travels faster in a medium only because its particles are closer together.” The better view is that sound speed depends on

41. A string fixed at both ends and a pipe open at both ends both have fundamental frequency in their ideal forms. The reason this same expression appears is that

42. Two sound waves of equal amplitude have frequencies and . The beat period and approximate pitch frequency are respectively

43. A fixed string of length has linear mass density and is stretched by tension . Its second harmonic frequency is closest to

44. A table compares common features of two wave representations. Select the row that is mismatched.

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

46. A pulse travelling along a string reaches a rigid wall where the end of the string is fixed. The reflected pulse is

47. Two waves reaching a point are represented by and , where and are close. The resultant displacement can be written in the form

48. Two pipes have the same length and contain air at the same temperature. Pipe P is open at both ends, while pipe Q is closed at one end. Their fundamental frequencies satisfy

49. A closed pipe resonates at in its fundamental mode. The next two higher resonant frequencies are

50. A sinusoidal wave has amplitude and angular frequency . The maximum acceleration of a medium particle is