Acoustics One Mark Online Test

Acoustics One Mark Online Test (10th Standard Science)

Pick how many questions you want and set a time limit, then start. You'll get your score at the end with the correct answer and an explanation for every question. Free, in Tamil and English — 22 questions available.

Set up your test

Number of questions

Time limit

Time remaining00:00

When a sound wave travels through air, the air particles

A.vibrate along the direction of the wave motion B.vibrate but not in any fixed direction C.vibrate perpendicular to the direction of the wave motion D.do not vibrate

Velocity of sound in a gaseous medium is 330 ms–1. If the pressure is increased by 4 times without causing a change in the temperature, the velocity of sound in the gas is

A.330 ms–1 B.660 ms–1 C.156 ms–1 D.990 ms–1

The frequency, which is audible to the human ear is

A.50 kHz B.20 kHz C.15000 kHz D.10000 kHz

The velocity of sound in air at a particular temperature is 330 ms–1. What will be its value when temperature is doubled and the pressure is halved?

A.330 ms–1 B.165 ms–1 C.330 × √2 ms–1 D.320 / √2 ms–1

If a sound wave travels with a frequency of 1.25 × 10⁴ Hz at 344 ms–1, the wavelength will be

A.27.52 m B.275.2 m C.0.02752 m D.2.752 m

The sound waves are reflected from an obstacle into the same medium from which they were incident. Which of the following changes?

A.speed B.frequency C.wavelength D.none of these

Velocity of sound in the atmosphere of a planet is 500 ms–1. The minimum distance between the sources of sound and the obstacle to hear the echo, should be

A.17 m B.20 m C.25 m D.50 m

Which of the following statements correctly describes the propagation of sound waves?

A.Sound waves travel as longitudinal waves in gases and transverse waves in solids. B.Sound waves can propagate through all states of matter as longitudinal waves. C.Sound waves do not require a material medium and can travel through vacuum. D.Sound waves travel fastest in gaseous media due to their high elasticity.

If the atmospheric pressure is increased by four times while the temperature of the air is kept constant, what happens to the velocity of sound?

A.It becomes four times its original value. B.It is halved. C.It remains unchanged. D.It is doubled.

Q10

When a longitudinal sound wave traveling in air strikes a rigid wall, how is the compression of the wave reflected?

A.It is reflected back as a rarefaction. B.It is reflected back as a compression. C.It is completely absorbed by the wall. D.It is converted into a transverse crest.

Q11

When a longitudinal wave traveling in a solid strikes the interface of a rarer medium like air, what happens to the compression?

A.It is reflected back as a compression. B.It is reflected back as a rarefaction. C.It is refracted without reflection. D.It is converted into a transverse trough.

Q12

Why does the speed of sound in air increase as the relative humidity of the air increases?

A.Humid air is denser than dry air, which increases the speed of sound. B.Humid air is less density than dry air, which increases the speed of sound. C.Water molecules in humid air act as resonators to amplify the wave. D.The presence of humidity always increases the temperature of the air.

Q13

If the velocity of sound in a planet's atmosphere is \(800\text{ ms}^{-1}\), what is the minimum distance between the source of sound and an obstacle to hear a distinct echo?

A.40.0 m B.20.0 m C.80.0 m D.17.2 m

Q14

What is the specific geometric shape of the walls in a whispering gallery, such as the one in St. Paul's Cathedral in London, that allows sound to travel long distances through multiple reflections?

A.Parabolic B.Spherical C.Elliptical D.Hyperbolic

Q15

A stationary sound source is positioned at the center of a circular path. If an observer moves along this circular path at a constant speed, what is the apparent frequency heard by the observer?

A.It increases continuously as the observer moves. B.It remains equal to the actual frequency of the source. C.It decreases continuously as the observer moves. D.It fluctuates periodically above and below the actual frequency.

Q16

Under which of the following circumstances will there be no Doppler effect, meaning the apparent frequency heard by a listener is exactly equal to the source frequency?

A.When the source is at rest and the listener moves toward it. B.When the listener is at rest and the source moves away from it. C.When the source and the listener move in mutually perpendicular directions. D.When both the source and the listener move toward each other.

Q17

Where is a speaker positioned relative to a curved concave sound board in an auditorium to ensure the sound is reflected parallelly toward the audience?

A.At the center of curvature of the concave board. B.At the focus of the concave board. C.Directly in contact with the concave board. D.At any arbitrary position behind the board.

Q18

Which of the following devices is a hearing aid designed with one wide end and one narrow end to concentrate sound entering the ear canal through multiple reflections?

A.Megaphone B.Ear trumpet C.Sound board D.Stethoscope

Q19

Which of the following types of sound waves cannot be heard by the human ear because their frequency is below the audible range?

A.Audible waves B.Ultrasonic waves C.Infrasonic waves D.Radio waves

Q20

Using the speed of sound values given in the textbook, arrange copper, water, and air (at 20 °C) in decreasing order of their sound velocities.

A.Water > Copper > Air B.Copper > Water > Air C.Air > Water > Copper D.Copper > Air > Water

Q21

For a gaseous medium, how does the velocity of sound waves vary with its absolute temperature (\(T\))?

A.It is directly proportional to \(T\). B.It is directly proportional to the square root of \(T\). C.It is inversely proportional to \(T\). D.It is independent of temperature.

Q22

In marine navigation, how is the Doppler effect utilized in SONAR systems?

A.To measure the salinity of seawater. B.To determine the speed of marine animals and submarines. C.To capture high-resolution images of the seabed. D.To measure the temperature of seawater at different depths.

More for this chapter

About this Acoustics test

This free online practice test covers Acoustics from the 10th Standard Science (Samacheer Kalvi) syllabus. Choose the number of questions and an optional time limit, then answer and submit — everything is checked in your browser, with the correct answers and a worked explanation shown at the end. For the full solutions to every question in this set, see the solved MCQs page.

More chapters in Science

View all