Resonance Column Experiment Viva Questions and Answers
1. What are stationary waves?
Ans: When two waves of the same frequency and amplitudes travel in opposite directions along a straight line at the same speed, their super position gives rise to stationary waves
2. What are nodes and antinodes?
Ans: Node is a position of zero displacement and antinode is a position of maximum displacement
3. In a stationary wave what is the distance between successive nodes?
Ans: λ/2, where λ is the wave length.
4. What is end correction or edge effect?
Ans: The antinode at the open end of a tube is formed slightly out side the open end. The distance from the open end to the antinode is called end correction e = 0.3d where d is the diameter of the pipe
5. What is meant by resonance?
Ans: When two notes of the same frequency are sounded together the intensity of sound is maximum and they are said to be in resonance or in unison
6. The experiment is called resonance column experiment why?
Ans: When we excite a tuning fork and hold it at the mouth of the tube at resonance the frequency of the air column and the frequency of the turning fork are equal. We obtain the frequency of the air column by resonance method
7. What is the effect of temperature on the velocity of sound in air?
Ans: The velocity of sound in air is directly proportional to the square root of temperature in Kelvin scale v ∝ √T.
8. In a resonance column experiment what is the functions of water in the jar?
Ans: It only acts as an agent for closing the tube to make the tube a closed tube of easily variable length
9. What is meant by supersonic speed?
Ans: The speed greater than that of sound in air ie, 331 m/s at 0°C
10. If we take kerosene oil in place of water in the resonance column experiment will the resonance position change?
Ans: Remains unchanged
11. Why is second resonance feebler than the first?
Ans: At second resonance the vibration in the air column corresponds to the first overtone which is very week
12. What type a waves you get in resonance column?
Ans: Longitudinal
13. Is it necessary to have a tube of circular cross section?
Ans: Not necessary.
14. What do you mean by the frequency of a tuning fork?
Ans: It is the number of vibrations made per second by either of the prongs.
15. What do you mean by the number 512 printed on the tuning fork?
Ans: It means that the prongs vibrate 512 times in one second.
16. Why are the forks made of some standard frequencies like 256, 288, 320, 314.5, 384, 426, 484, 512 Hz?
Ans: These are frequency identical with those of the major diatomic scale which is a musical scale C D E F G A B C’.
17. What type waves are the sound waves?
Ans: Longitudinal waves
18. What are longitudinal waves?
Ans: Longitudinal waves are those waves in which particles of the medium vibrate parallel to the direction of propagation of the waves.
19. What are nodes and antinodes?
Ans: Nodes are points of zero amplitude and antinodes are points of maximum amplitude.
20. What are the factors depend on the velocity of sound waves?
Ans: Temperature of the medium and humidity
21. Explain resonance?
Ans: The phenomenon of producing vibrations in a body by a second vibrating body of same natural frequency as that of the first is called resonance.
22. Define wavelength (λ)
Ans: It is the distance travelled by a wave during that time the particles in the medium complete one vibration.
23. How does the temperature variation affect the velocity of sound?
Ans: The velocity of sound increases with temperature.
ie, v ∝ √T, where T is the temperature in Kelvin Scale.
24. How does the variation of humidity affect the velocity of sound?
Ans: Velocity of sound in humid air is more than that in dry air.
ie, v ∝ √(1/ρ), where ρ is the density of air
25. The vibrations of a fork stop when its prongs are touched but they do not stop if the stem is touched. Why?
Ans: This is because the prongs are vibrating perpendicular to their length whereas the stem is vibrating along its length.
26. In which medium is the velocity of sound higher, in oxygen or in hydrogen?
Ans: In hydrogen its velocity is higher because velocity of sound is inversely proportional to the square root of density of the medium. Hydrogen has lower density than oxygen and thus sound will have higher velocity in hydrogen.
27. What is the resonance column apparatus?
Ans: Resonance column is an apparatus by means of which the wavelength of sound waves in air can be determined by throwing a particular length of air column into resonant vibrations.
28. What is the role of water in resonance column apparatus?
Ans: It acts as a rigid wall for the reflection of sound waves.
29. What type of waves are produced in resonance column apparatus?
Ans: Longitudinal stationary waves.
30. What are the nodes and antinodes situated?
Ans: Node is at the water surface and antinode at the open end of the tube.
31. What is meant by 'end correction'?
Ans: The antinode at the open end of the tube does not coincide exactly with the open end of the tube, but projects slightly outside it by a small distance, called the end correction.
32. Aim of Resonance Column experiment?
Ans: (a) To determine the velocity of sound in air at room temperature by the resonance column and hence to determine the velocity of sound in air at 0°C.
(b) To find the end correction.
33. Apparatus for the Resonance Column experiment?
Ans: Resonance column apparatus, tuning forks, rubber hammer etc. Resonance column apparatus includes a long metal tube erected vertically in a tall jar containing water. The tube can be set in any desired position. The length of the air column in the tube can be varied by stretching or lessening the tube.