When a sound is reflected from a distant object, an echo is produced. Let the distance between the reflecting surface and the source of sound production remains the same. Do you hear echo sound on a hotter day?
Solution and Explanation
The occurrence of an echo is dependent on a time interval of at least 0.1 seconds between the reflected sound and the original sound. As the temperature rises, the speed of sound in a medium increase. Consequently, on a warmer day, the time interval between the reflected and original sound decreases. An echo is audible only if the time interval between the reflected sound and the original sound is greater than 0.1 s.
Top Questions on Reflection of Sound
- Which of the following statements are true for "Sound" ?
- WBJEE JENPAS UG - 2022
- Physical Sciences
- Reflection of Sound
- Give two practical applications of reflection of sound waves.
- CBSE Class IX
- Science
- Reflection of Sound
- What is reverberation? How can it be reduced?
- CBSE Class IX
- Science
- Reflection of Sound
- Does sound follow the same laws of reflection as light does? Explain.
- CBSE Class IX
- Science
- Reflection of Sound
Questions Asked in CBSE Class IX exam
- Narrate two incidents that show how differences can be created, and also how they can be resolved. How can people change their attitudes?
- CBSE Class IX
- My childhood
- Einstein got ever more involved in politics, agitating for an end to the arms buildup. (campaigning, fighting, supporting)
- CBSE Class IX
- A truly beautiful mind
A driver of a car travelling at \(52\) \(km \;h^{–1}\) applies the brakes Shade the area on the graph that represents the distance travelled by the car during the period.
Which part of the graph represents uniform motion of the car?- CBSE Class IX
- Graphical Representation of Motion
- Rewrite the sentences below, changing the verbs in brackets into the passive form.
1. In yesterday’s competition the prizes (give away) by the Principal.
2. In spite of financial difficulties, the labourers (pay) on time.
3. On Republic Day, vehicles (not allow) beyond this point.
4. Second-hand books (buy and sell) on the pavement every Saturday.
5. Elections to the Lok Sabha (hold) every five years.6. Our National Anthem (compose) Rabindranath Tagore.- CBSE Class IX
- My childhood
In Fig. 9.26, A, B, C and D are four points on a circle. AC and BD intersect at a point E such that ∠ BEC = 130° and ∠ ECD = 20°. Find ∠ BAC.
- CBSE Class IX
- Angle Subtended by an Arc of a Circle
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.