Waves | Physics
Conceptual Questions Answers
1. Why is it that transverse waves cannot be produced in a gas?. Can the transverse waves can be produced in solids and liquids?
Answer: Transverse waves travel in the form of crests and troughs and so involve change in shape. As gas has no elasticity of shape, transverse waves cannot be produced in it.
2. Why is the roar of our national animal different from the sound of a mosquito?
Answer: Roaring of a national animal (tiger) produces a sound of low pitch and high intensity or loudness, whereas the buzzing of mosquito produces a sound of high pitch and low intensity or loudness.
3. A sound source and listener are both stationary and a strong wind is blowing. Is there a Doppler effect?
Answer: Yes. It does not matter whether there is sound I source or transmission media in motion.
4. In an empty room why is it that a tone sounds louder than in the room having things like furniture etc.
Answer: Sound is a form of energy. The furniture which act as obstacles absorbs most of the energy. So the intensity of sound become low but in empty room, due to the absence of obstacles the intensity of sound remain mostly same and we feel it louder.
5. How do animals sense impending danger of hurricane?
Answer: Some animals are believed to be sensitive to low frequency sound waves emitted by hurricanes. They can also detect the slight fall in air pressure, and water pressure that signal a storm's approach.
6. Is it possible to realize whether a vessel kept under the tap is about to fill with water?
Answer: The frequency of the note produced by an air column is inversely proportional to its length. As the level of water in the vessel rises, the length of the air column above it decreases. It produce, sound of decreasing frequency, i.e., the sound becomes shorter. From the shrillness of sound, is possible to realize whether the vessel is filled with water.
vmin = 11.71 ms-1