Why is sound wave called a longitudinal wave?
Solution and Explanation
A longitudinal wave refers to vibrations in the medium that travel along or parallel to the direction of the wave. In the case of a sound wave, particles of the medium vibrate in a direction parallel to the propagation of disturbances.
Therefore, a sound wave is appropriately termed a longitudinal wave.
Top Questions on Propagation of Sound
- A sound wave travels at a speed of 339 ms–1. If its wavelength is 1.5 cm, what is the frequency of the wave? Will it be audible?
- CBSE Class IX
- Science
- Propagation of Sound
- What is loudness of sound? What factors does it depend on?
- CBSE Class IX
- Science
- Propagation of Sound
- A stone is dropped from the top of a tower 500 m high into a pond of water at the base of the tower. When is the splash heard at the top?
Given, g = 10 ms–2 and speed of sound = 340 ms–1.- CBSE Class IX
- Science
- Propagation of Sound
- The frequency of a source of sound is 100 Hz. How many times does it vibrate in a minute?
- CBSE Class IX
- Science
- Propagation of Sound
- Flash and thunder are produced simultaneously. But thunder is heard a few seconds after the flash is seen, why?
- CBSE Class IX
- Science
- Propagation of Sound
Questions Asked in CBSE Class IX exam
- Calculate how many years and months ahead from now Margie’s diary entry is.
- CBSE Class IX
- The fun they had
- What are the main features of the mechanical teachers and the schoolrooms that Margie and Tommy have in the story?
- CBSE Class IX
- The fun they had
Use these adverbs to fill in the blanks in the sentences below.
awfully sorrowfully completely loftily carefully differently quickly nonchalantly(i) The report must be read ________ so that performance can be improved.
(ii) At the interview, Sameer answered our questions _________, shrugging his shoulders.
(iii) We all behave _________ when we are tired or hungry.
(iv) The teacher shook her head ________ when Ravi lied to her.
(v) I ________ forgot about it.
(vi) When I complimented Revathi on her success, she just smiled ________ and turned away.
(vii) The President of the Company is ________ busy and will not be able to meet you.
(viii) I finished my work ________ so that I could go out to play
- CBSE Class IX
- The fun they had
- Is there any difference between the two roads as the poet describes them:
(i) in stanzas two and three?
(ii) in the last two lines of the poem?- CBSE Class IX
- The fun they had
- Here is your diary entry when you visited Agra. Read the points and try to write a travelogue describing your visit to Agra and the Taj Mahal. You may add more details.
January 2003 — rise before dawn — take the Shatabdi Express at 6.15 a.m. from Delhi — meet a newly-married couple on train — talk about Himachal Pradesh — get off the train — enter the once-grand city, Agra — twisted alleys — traffic dense — rickshaws, cars, people — vendors selling religious artifacts, plastic toys, spices and sweets — go to the Taj Mahal — constructed entirely of white marble — magical quality — colour changes with varying of light and shadow — marble with gemstones inside — reflection of the Taj Mahal in the pond — school-children, tourists — tourist guides following people.- CBSE Class IX
- Kathmandu
Concepts Used:
Sound
Sound is a vibration that propagates the mechanical wave of displacement and pressure, through a medium can be of any matter. In other words, the sound is the thin line between Music sound and Noise.
Types of Sounds:
Sound can be divided into two types depending on its frequency. The following are:-
Infrasonic Waves:
- Infrasonic waves have a frequency lower than 20 Hz. Since it is below the human hearing range, it is inaudible to humans.
- However, several other living organisms use these waves to communicate, whales, sharks, elephants, hippopotamus, etc. these waves are also used in the scientific field, it is used to study upcoming earthquakes, volcanic eruptions, human heart rates, rock formation stages, etc.
Ultrasonic waves:
- Ultrasonic waves have a frequency higher than 20 kHz. Since it is above the human hearing range, it is inaudible to humans.
- These waves are used in the scientific field, it is used to study human heart rates, to take sonograms, navigation of directions, imaging things, uniform sample mixing, communication, testing of samples, etc.