Physics XI Karachi Board True and False - Chapter 8

Chapter 8 - Wave Motion and Sound
1. In SHM acceleration is proportional to displacement and is directed towards mean position.

2. SHM is a motion under elastic-restoring force.

3. In SHM the system must have friction.

4. The motion of the particle moving in a circle is SHM.

5. The motion of the projection of a particle moving in a circle along one of its diameter is simple harmonic.

6. The motion of a simple pendulum is always SHM.

7. The motion of simple pendulum may be simple harmonic.

8. The time period of a simple pendulum increases with its length.

9. The time period of a simple pendulum changes from place to place.

10. Kinetic energy of a system executing SHM is always conserved.

11. Potential energy of a system executing SHM is always conserved.

12. Total energy of system executing SHM is always conserved.

13. The total energy of a particle executing SHM is directly proportional to the frequency of oscillation.

14. The total energy of a particle executing SHM is directly proportional to square of its amplitude of oscillation.

15. If pendulum is transported to moon. It will go fast.

16. The particle velocity is minimum at the nodal points in a stationary waves.

17. The distance between any two successive nodes in a stationary waves is equal to a quarter of its wavelength.

18. Sound waves can travel through water.

19. Sound waves travel faster in air then iron.

20. In dense atmosphere of gases, sound waves travel faster in air then iron.


21. The velocity of sound in a fluid medium varies directly as its absolute temperature.

22. The change in pressure and volume of a gas due to propagation of a sound wave through it is isothermal.

23. In a closed organ pipe, a node is formed at the close end.

24. When the intensity of sound wave is great, its loudness is also great.

25. In debating halls, it is good to have low flat ceiling.

26. The velocity of sound in air is directly proportional to the pressure of air.

27. The frequency of transverse vibration in a sonometer is doubled when the tension is increased four times, keeping other factors constant.

28. The pitch of a sound note decreases as the source of sound approaches the observer.

29. The pitch of a sound note increases as both source and listener move towards each other.

30. The frequency of the beats produced by two simultaneously exicited turning forks decreases when the tuning fork of higher frequency is loaded with little wax.

31. Normal human ear can detect upto twenty beats per second.

32. The pitch of a musical note increases with the amplitude of vibration.

33. When stationary waves are produced in a stretched string, the tension is maximum at the nodes.

34. In case of stationary waves produced in a stretched string, the tension is maximum at the nodes.

35. In case of stationary waves produced in a stretched string, first multiple is equal to second harmonic.

36. In case of sonometer, the velocity of standing waves produced is directly proportional to the mass per unit length of vibrating wire.

37. Laplace’s correction was suggested in Newton’s formula due to fact that propagation of sound waves through air is adiabatic.

38. The terms quality and timber are used for the same property.

39. When two tuning forks of frequencies 256Hz and 259 Hz, excited together and are sounded simultaneously. The frequency of beats produced is 6.

40. The term acoustics is used to describe the way in which sound is reproduced in practical situations.

41. The standing waves are produced due to exactly similar progressive waves travelling through any medium in the same direction.

42. The simple pendulum comes to rest after some time due to the pull of earth.

43. When sound waves strike a hard surface, they are completely absorbed.

44. The sound waves are longitudinal in nature.

45. The sound waves are electromagnetic waves.