C-07 — Waves and Sound

According to Hooke's law, the restoring force of a spring with constant $k$ at displacement $x$ from equilibrium is

Harmonic or oscillatory motion that obeys Hooke's law is called

For a mass $m$ attached to a spring of constant $k$, the time period is

For a simple pendulum of length $l$ with gravitational acceleration $g$, the time period is

The time period of a simple pendulum does NOT depend on

The time period of a 1 m long pendulum (taking $g = 9.8\,\text{m/s}^2$) is approximately

The time required for one complete oscillation is called

The number of complete oscillations per second is called

The unit of frequency is

The relation between frequency $f$ and time period $T$ is

In simple harmonic motion, the amplitude is

In simple harmonic motion, the phase of a body at any instant refers to

In simple harmonic motion, energy is exchanged between

An oscillating spring eventually stops because of

After how long does the phase of a particle in simple harmonic motion return identically?

A wave is best defined as

A series of repeated disturbances generates

A wave that needs a gaseous, liquid or solid medium to travel through is called

Which of the following is a mechanical wave?

Which of the following is an electromagnetic wave?

Electromagnetic waves require

When a mechanical wave passes through a medium, the particles of the medium

The energy carried by a wave is proportional to

If the amplitude of a wave is doubled, its energy becomes

The velocity of sound in air is approximately

The velocity of sound in water is approximately

The velocity of a wave on a tight (taut) rope compared to a loose rope is

Hearing the echo of a sound is an example of

Hearing an external sound while submerged under water is due to

The most important characteristic of waves is

When two waves of equal magnitude but opposite signs meet, they

In a longitudinal wave, the direction of vibration of medium particles is

Sound waves are

A longitudinal wave propagates by

In a transverse wave, the direction of vibration of medium particles is

The wave produced on a rope by shaking one end is

A water wave is an example of

The wavelength of a wave is

The distance traveled by a wave in one second is called

The relation between wave velocity $v$, frequency $f$, and wavelength $\lambda$ is

When a wave travels from one medium to another, the quantity that does NOT change is

From a graph of a wave plotted against position only, one can determine

From a graph of a wave plotted against time only, one can determine

A wave has wavelength 1 m and time period 0.2 s. Its frequency is

A wave has wavelength 1 m and frequency 5 Hz. Its velocity is

A 1 kHz sound passes through air at 334 m/s. Its wavelength in air is

The same 1 kHz sound passes through water at 1493 m/s. Its wavelength in water is

The same 1 kHz sound passes through iron at 5130 m/s. Its wavelength in iron is

Sound is produced by

To produce and hear a sound, what is required?

In humans, sound is created by the vibration of

Why is the voice of a male coarse (low frequency)?

The voice of a female is high pitched because

The bell-jar experiment with an electric bell shows that

The audible range of frequency for normal human ears is

Sound of frequency below 20 Hz is called

Sound of frequency above 20 kHz is called

Before earthquakes, animals often panic because they hear

Sound is called a mechanical wave because its propagation requires

Sound is a longitudinal wave because

The velocity of sound is greatest in

The velocity of sound in a medium depends on

The intensity of sound is proportional to

Like other waves, sound waves can undergo

An echo of sound is produced by

The persistence of hearing in the human ear is approximately

Taking the velocity of sound as 330 m/s, the minimum distance from a reflecting surface for a distinct echo is approximately

Bats can fly without colliding with obstacles in the dark because they use

Bats can produce sound of frequency about

In air, the velocity of sound is proportional to

The velocity of sound in air and the air pressure are

The velocity of sound in air is inversely proportional to

As humidity in air increases, the velocity of sound in air

At 10°C the velocity of sound in air is 338 m/s. At 30°C its velocity will be approximately

The velocity of sound in any medium primarily depends on

The fetus inside a pregnant mother's womb is examined by a process called

To explore for gas or oil below the earth's surface one uses

The receiver used to detect reflected waves in a seismic survey is called a

An ultrasound cleaner removes dirt from small instruments by

Musical sound differs from a single tuning-fork sound because it consists of

A tuning fork produces

Which of the following is a string (wire) instrument?

Which of the following is an air-flow (wind) instrument?

Which of the following is a percussion instrument?

Excessive, unwanted sound that disturbs life is called

A primary effect of long-term sound pollution is

Which step does NOT help reduce sound pollution?

Trees planted in empty places of cities help reduce sound pollution because they

What type of wave is sound?

In which medium is the velocity of sound maximum?

Why is a dead bat seen hanging from an electric line?

In Figure 7.16 with sound source S above the water surface AB, taking the speed of sound as 332 m/s, what is the maximum value of $h$ for which an echo can be heard?

For the same Figure 7.16 with $h = 10$ m, how much time is required to hear the echo?

Why is the velocity of sound greater in water than in air?

A factory's alarm sound travels 16.6 m to reach Navid's house. Taking the speed of sound as 332 m/s, the time taken is

Navid, who lives 16.6 m from a noisy factory, recently developed headaches and insomnia. The most likely cause is

Periodic motion is best defined as

A water wave is a transverse wave because

Sound of frequency 1200 Hz travels in air at 30°C; speed of sound at 0°C is 332 m/s. The wavelength of the sound is approximately

Source S is 18 m from a reflecting surface; speed of sound at 30°C is about 349.85 m/s. Will an echo be heard at S?

Speed of sound at 0°C is 332 m/s. In summer at 30°C the speed of sound is approximately

Farhan, standing 17.25 m from a wall, hears an echo on a winter day at 10°C but not on a summer day at 30°C. The reason is

Which of the following is a correct difference between longitudinal and transverse waves?

A simple pendulum exhibits which type of motion?

For a clear echo to occur, the reflecting surface must be

Why must the reflecting surface for an echo be large?

The swaying of a paddy field by air creates which kind of wave?