Waves Mock Test – Class 11 Physics

1. Two sounds travel through the same medium and have the same frequency, but sound P has larger amplitude than sound Q. The most direct wave-based difference is that sound P is

2. A train moving toward a stationary observer emits , and the observer hears . If the speed of sound is , the train speed is closest to

3. The unit is naturally associated with

4. A sinusoidal wave on a string is , with SI units. The string has . If the amplitude is later increased by and the angular frequency is reduced to of its original value on the same string under the same tension, the new average power compared with the original becomes

5. 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

6. 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

7. An open pipe of physical length has end correction at each end. A closed pipe of physical length has the same end correction at its open end. Both contain air with sound speed . The ratio of their fundamental frequencies is closest to

8. A source emits sound of frequency while moving toward a stationary observer with speed . In the same gas, the speed of sound is at . If the gas is heated to and the source speed remains unchanged, the new frequency heard by the observer is closest to

9. A sound wave travels through a medium where particles are difficult to compress but also have large inertia. A careful prediction of sound speed should consider

10. For a right-moving wave , the relation between particle velocity and wave-profile slope is

11. 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

12. Linear mass density of a string is defined as

13. A source moves away from a stationary observer. A student uses and obtains a higher frequency. The correction is that the denominator should be

14. In a plane sound wave, the pressure variation is related to the particle displacement by the spatial change of . A suitable local relation is

15. A point on a string has zero transverse velocity at a certain instant in a sinusoidal travelling wave. Its displacement is most likely

16. In a progressive sinusoidal wave, the phase may contain the term . The role of is to represent

17. A resonance curve is drawn for an air column. The vertical axis shows amplitude of vibration, and the horizontal axis shows driving frequency. A sharp peak occurs when the driving frequency is

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

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

The mismatched row is

20. A travelling disturbance has shape at . After time , the same shape has shifted a distance toward positive without changing form. Its displacement can be written as

21. A supersonic aircraft moves at . The Mach cone semi-angle is . The speed of sound in the air around it is

22. Two strings are under the same tension. String P has linear mass density , and string Q has linear mass density . If the speed on P is , the speed on Q is

23. A stationary observer listens to a source moving toward the observer with speed . If the speed of sound in air is and the source frequency is , the observed frequency is

24. Read the passage and answer the question.

What does the coloured mark help identify?

25. In a closed resonance tube, the measured first and second resonance lengths are and . Which conclusion is safest without knowing the end correction?

26. A progressive wave on a string has the same amplitude at all positions, while a standing wave has amplitude depending on position. This difference occurs because

27. A claim says, “When a wave enters a new medium, its frequency must change because its speed changes.” The best correction is that

28. A sound wave travelling through air is called a mechanical wave because

29. A source moves through air with speed , greater than the sound speed . The Mach number is

30. A longitudinal sound wave has displacement . The pressure variation is proportional to

31. Study the table and identify the row that is not suitable.

32. A wave is described by . How far does a fixed phase point of this wave move in ?

33. A particle of a medium completes one oscillation in . What is the frequency of the wave motion at that point?

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

35. In a sound wave, a pressure maximum and a displacement maximum do not occur at the same position because

36. A string fixed at both ends vibrates in a mode whose neighbouring nodes are apart. If the wave speed on the string is , the frequency of the wave is

37. Two points in adjacent loops of a standing wave on a string have their displacements at the same instant compared. If one loop is displaced upward, the adjacent loop is

38. A tuning fork produces resonance in a closed tube at lengths and . Neglecting end correction, the speed of sound is

39. A closed pipe has fundamental frequency . An open pipe in the same air has length times the closed pipe length. Neglecting end correction, the fundamental frequency of the open pipe is

40. A claim says, “A string fixed at both ends can vibrate only in odd harmonics.” The best correction is that

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

42. Use the graph description below.

The beat frequency is

43. The equation represents a sinusoidal wave travelling in

44. 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

45. For an ideal gas, the speed of sound may be written as . At the same temperature and with the same , the gas with smaller molar mass has

46. Study the table for a sinusoidal sound wave and identify the mismatched row.

47. 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

48. A progressive wave is given by , with SI units. The maximum particle speed is

49. Two media are compared for sound propagation. Medium P has a stronger elastic restoring effect but similar inertia compared with medium Q. The sound speed in P is expected to be

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