Wave in pipes and strings | Old is Gold | Class XII



Wave in pipes and strings

Short

1. The frequency of fundamental note of an open organ pipe is double than for closed pipe of same length. Why?

2. Differentiate between forced vibration and free vibration.

3. The frequency of organ pipe changes with temperature. Does it increases with increase in temperature?

4. Explain why soldiers are ordered to break steps while crossing a bridge.

5. Why is an end correction necessary for an organ pipe?

6. Relate the fundamental note with overtones for an open pipe.

7. Why is monometer box hollow from inside?

8. What do you mean by resonance?

9. Why does an empty vessel produce more sound then a filled one?

10. One of the `Nine Jewels` of Emperor Akbar, widely, known as Tansen, the king of Music was able to break a glass by singing the appropriate note. What physical phenomenon could account for this?

11. How does the temperature affect the frequency of an organ pipe?

12. Why are rubbers used as vibration absorber?

13. Why are all string instruments provided with hollow boxes?

14. What is the use of sounding board on stringed musical instrument?

15. Would you expect the pitch of an organ pipe to change with an increase in temperature? How?

16.  Is the wave speed the same as the speed of any part of the string for transverse waves? Explain the difference between these two speeds?

17. Why are the bells made of metal not of wood?

18. When tension in a given stretched string is increased by four times, by what factor does the velocity of transverse wave in the string change?

19. If the frequency of a fundamental note of a closed pipe and that of an open pipe are the same, what will be the ratio between their lengths?

20. A loud in heard at resonance. Why?

21. Is it possible to have a longitudinal wave on a stretched string? Why or why not?

Long

1. Describe the various modes of the air column in an organ pipe?

2. Describe the various modes of vibration of the air column in a closed organ pipe?

3. Prove that both types of harmonics, odd and even, can be produced in an organ pipe open at both ends.

4. State the laws of transverse vibrations of string. Using only dimensions show that the speeds of propagation of a transverse wave depend only on tension and mass per unit length.

5. State the laws of transverse vibration of string. Describe an experiment to verify the law of mass, and law of length.

6. Discuss the different modes of vibrations of air column in closed pipe.

7. State and explain principle of superposition and formation of stationary waves. Show that the frequency of the fundamental note of a closed organ pipe is half as compared to that of an open pipe of the same length.

8. What do you understand by `harmonics` and `overtone` in the case of organ pipe. Also prove that only odd harmonics are produced in closed ended organ pipe.

9. Describe an experiment giving the necessary theory by which the speed of sound in air medium determined using resonance air column method.

10. Describe the resonance tube experiment to determine the velocity of sound in Laboratory and obtain the expression of end correction.

11. What is a closed pipe? Describe the natural modes of vibration of air in an organ pipe closed at one end. Also explain the term `end correction`.

12. What is meant by resonance? Explain in detail how you would use monometer to determine frequency of a given tuning fork.

13. What are harmonics? Explain the formation of the overtones in a closed organ pipe.