Consider the following statements regarding the speed of sound: 1. Speed of sound in air at 0°C is 500 m/s. 2. Speed of sound in air at 22°C is 344 m/s. 3. Speed of sound in water is greater than in air. Which of the statements given above are correct?

The correct option is (c) 2 and 3 only. Explanation The speed of sound depends on the properties of the medium through which it propagates, primarily its elasticity and density, as well as physical conditions such as temperature. - Statement 1 is Incorrect: The speed of sound in dry air at 0°C is approximately 331 m/s. The value of 500 m/s is factually incorrect. - Statement 2 is Correct: The speed of sound in air is directly proportional to the square root of the absolute temperature. As temperature increases, the speed of sound increases. At a temperature of 22°C, the speed of sound in air is approximately 344 m/s. - Statement 3 is Correct: Sound travels faster in denser media where particles are closer together, facilitating rapid energy transfer. Consequently, the speed of sound is faster in liquids than in gases. For instance, the speed of sound in water is approximately 1500 m/s, which is significantly higher than in air. Key Takeaway: The speed of sound generally follows the order Solids > Liquids > Gases. In gases, the speed increases by approximately 0.61 m/s for every 1°C rise in temperature.

NCERT Class 9 Science — Chapter 5: Sound

mcqmedium

Consider the following statements regarding the speed of sound:

Speed of sound in air at 0°C is 500 m/s.
Speed of sound in air at 22°C is 344 m/s.
Speed of sound in water is greater than in air.

Which of the statements given above are correct?

Official previous-year question

Verified 1 Aug 2026.

Options

A1 and 2 only
B2 only
C2 and 3 only
D1, 2 and 3

Did you get this right?

Solution

The correct option is (c) 2 and 3 only.

Explanation

The speed of sound depends on the properties of the medium through which it propagates, primarily its elasticity and density, as well as physical conditions such as temperature.

Statement 1 is Incorrect: The speed of sound in dry air at 0°C is approximately 331 m/s. The value of 500 m/s is factually incorrect.
Statement 2 is Correct: The speed of sound in air is directly proportional to the square root of the absolute temperature. As temperature increases, the speed of sound increases. At a temperature of 22°C, the speed of sound in air is approximately 344 m/s.
Statement 3 is Correct: Sound travels faster in denser media where particles are closer together, facilitating rapid energy transfer. Consequently, the speed of sound is faster in liquids than in gases. For instance, the speed of sound in water is approximately 1500 m/s, which is significantly higher than in air.

Key Takeaway: The speed of sound generally follows the order Solids > Liquids > Gases. In gases, the speed increases by approximately 0.61 m/s for every 1°C rise in temperature.

Your note

More from Chapter 5: Sound

Consider the following statements regarding the propagation of sound: 1. The disturbance created by a source travels through the medium to the listener. 2. Sound waves are characterized as non-mechanical waves. 3. A material medium is mandatory for the transmission of sound. Which of the statements given above are correct?

medium

With reference to the characteristics of a sound wave, consider the following statements: 1. The distance between two consecutive compressions is called the wavelength. 2. The time taken for one complete oscillation is called the frequency. 3. The SI unit of frequency is Hertz. Which of the statements given above are correct?

medium

Consider the following statements regarding Ultrasound: 1. It refers to sounds with frequencies higher than 20 kHz. 2. Ultrasound waves scatter immediately when they encounter obstacles. 3. Ultrasound is incapable of penetrating metal blocks to detect flaws. Which of the statements given above is/are correct?

easy

The cleaning action of an ultrasonic cleaner is primarily achieved through:

medium

With reference to medical applications of sound, consider the following statements: 1. Echocardiography uses ultrasonic waves to form an image of the heart. 2. Ultrasonography uses X-rays to detect stones in the gall bladder. 3. Ultrasound can be used to break kidney stones into fine grains. Which of the statements given above are correct?

medium

Keep practising Chapter 5: Sound

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The correct option is (c) 2 and 3 only.

Explanation

The speed of sound depends on the properties of the medium through which it propagates, primarily its elasticity and density, as well as physical conditions such as temperature.

Statement 1 is Incorrect: The speed of sound in dry air at 0°C is approximately 331 m/s. The value of 500 m/s is factually incorrect.
Statement 2 is Correct: The speed of sound in air is directly proportional to the square root of the absolute temperature. As temperature increases, the speed of sound increases. At a temperature of 22°C, the speed of sound in air is approximately 344 m/s.
Statement 3 is Correct: Sound travels faster in denser media where particles are closer together, facilitating rapid energy transfer. Consequently, the speed of sound is faster in liquids than in gases. For instance, the speed of sound in water is approximately 1500 m/s, which is significantly higher than in air.

Key Takeaway: The speed of sound generally follows the order Solids > Liquids > Gases. In gases, the speed increases by approximately 0.61 m/s for every 1°C rise in temperature.