Chapter 12 – Sound

The sound can travel in air when:

We can distinguish between a man’s voice and a woman’s voice of the same loudness even without seeing them. This is due to a characteristic of sound which measures the shrillness of sounds. Can you choose the correct unit of the quantity on which this characteristic of sound depends?

A key of mechanical piano is first struck gently and then struck again but much harder this time. What kind of change in sound will you observe in the second case:

The echo-receiver of a sonar attached to a ship, receives the echo from the bottom of sea 4 seconds after the ultrasonic waves were sent into the sea.

If the speed of sound in water is 1500 m/s, then what is the depth of the sea?

Before the main shock waves, the earthquake produces the characteristic sound waves which some animals like rhinoceros can hear. Can you guess the kind of sound waves produced here?

Given below is the diagram of human ear.

Choose the correct labeling of the parts A, B and C.

On increasing the temperature, the speed of sound in air:

Loudness measures the sound energy reaching the ear per second and depends on the amplitude of the sound wave. What is the unit used to measure the loudness of sound?

We can easily distinguish between the sounds of the different singers even without having seen them. This is all due the different quality or timber of their sounds. On what factor does the quality of sound depend?

Before playing the orchestra in a musical concert, a sitarist tries to adjust the tension and pluck the string suitably. By doing so, he is adjusting
i. Amplitude of the sound
ii. Frequency of the sitar string with the frequency of other musical instruments
iii. Intensity of sound
iv. Loudness of sound

The bats can fly in the darkness of night without colliding with the other objects by emitting special sounds while flying. Which characteristic of sound is used by the bats to navigate?

The sound travels from particle to particle in the form of vibrations and has different speeds in different mediums.

The maximum speed of vibrations which produce audible sound will be in:

Which of the following can produce longitudinal as well as transverse waves under different conditions?

If the speed of a wave is 380 m/s and its frequency is 1900 Hz, then the wavelength of the wave will be:

You must have seen the doctor checking the sounds produced in the chest or heartbeat of a patient using a medical instrument called Stethoscope. On what principle does this Stethoscope work?

For hearing a distinct sound, the time interval between the original sound and the reflected one must be at least:

The persistence of sound in an auditorium is the result of repeated reflections of sound and is called:

The speed v, frequency υ, and wavelength λ, of sound are related by the equation:

The speed of sound is maximum in:

Our ears are sensitive to sound frequencies between:

Which of the following waves are produced by bats?

Maximum tolerable sound is:

Sound waves are:

In SONAR, we use:

Sound travels in the air if:

When we change feeble sound to loud sound we increase its:

In the curve half the wavelength is:

MCQ Questions for Class 9 Science Chapter 12 Sound Q12

An earthquake produces which kind of sound before the mainshock wave begins:

Infrasound can be heard by:

Fill in the blank