The depression or hollow formed below the mean level of the transverse wave is called the trough. Note: When vibrating particles of medium move upward, above the line of zero disturbance, they form an elevation or bump and when the vibrating particles of medium move downward, below the line of zero disturbance, they form a depression or hollow.

A longitudinal wave is produced on a toy slinky. The wave travels at a speed of 30 cm s and the frequency of the wave is 20 Hz . What is the maximum distance between the consecutive compressions of the slinky?

Given, Wave velocity, v = 30 cm s Frequency, f = 20 Hz We know that, v = f × λ ⇒ λ = v f ⇒ 30 20 = 1 . 5 cm The maximum distance between the consecutive compressions which is nothing but wavelength is 1 . 5 cm .

EASY

Earn 100

Define trough.

Important Questions on Waves and Sound

EASY

Physical and Earth Science>Relationships>Waves and Sound>Basic Terms in Wave Motion

If the speed of wave is

250 m / s

and its wavelength is

50 cm

then the frequency will be:

EASY

Physical and Earth Science>Relationships>Waves and Sound>Basic Terms in Wave Motion

The frequency of radio waves from a certain radio station is

600 KHz

. Its wavelength is

EASY

Physical and Earth Science>Relationships>Waves and Sound>Basic Terms in Wave Motion

The velocity of sound wave in a given medium is

V

when its frequency is

ν

. The velocity, when the frequency changes to

5 ν

is :

EASY

Physical and Earth Science>Relationships>Waves and Sound>Basic Terms in Wave Motion

If the speed of wave is

350 m / s

and its wavelength is

100 cm

then the frequency of the wave will be

HARD

Physical and Earth Science>Relationships>Waves and Sound>Basic Terms in Wave Motion

A ball is moving uniformly in a circular path of radius

1 m

with a time period of

1.5 s

. If the ball is suddenly stopped at

t = 8.3 s,

the magnitude of the displacement of the ball with respect to its position at

t = 0 s

is closest to:

EASY

Physical and Earth Science>Relationships>Waves and Sound>Basic Terms in Wave Motion

When sound is refracted from air to water, which of the following will remain unchanged?

MEDIUM

Physical and Earth Science>Relationships>Waves and Sound>Basic Terms in Wave Motion

Consider the following statements and select the correct alternative: Statement (A): The frequency of the sound wave whose wave length is

1.5 cm

with speed

339 m / s

22600 Hz

. Statement (B): The given sound is audible to human beings.

MEDIUM

Physical and Earth Science>Relationships>Waves and Sound>Basic Terms in Wave Motion

The given graph shows the displacement versus time relation for a disturbance travelling with velocity $1500 m / s$ . The wavelength of the disturbance will be

Question Image

EASY

Physical and Earth Science>Relationships>Waves and Sound>Basic Terms in Wave Motion

On an average, a human heart is found to beat

72

times a minute. Its frequency and period are

HARD

Physical and Earth Science>Relationships>Waves and Sound>Basic Terms in Wave Motion

A point particle is acted upon by a restoring force

- k x^{3} .

The time period of oscillation is

T

when the amplitude is

A .

The time period for an amplitude

2 A

will be:

EASY

Physical and Earth Science>Relationships>Waves and Sound>Basic Terms in Wave Motion

The speed of a wave in a medium is

760 {ms}^{- 1}

.If

3600

waves are passing through a point in the medium in

2

minutes then its wavelength is

EASY

Physical and Earth Science>Relationships>Waves and Sound>Basic Terms in Wave Motion

A simple wave motion is represented by $y = 5 (\sin 4 π t + \sqrt{3} \cos 4 π t)$ . Its amplitude is

MEDIUM

Physical and Earth Science>Relationships>Waves and Sound>Basic Terms in Wave Motion

What are acoustically measurable quantities related to pitch and loudness?

MEDIUM

Physical and Earth Science>Relationships>Waves and Sound>Basic Terms in Wave Motion

A transverse wave travels on a taut steel wire with a velocity of

v

when tension in it is

2.06 \times 10^{4} N .

When the tension is changed to

T,

the velocity changed to

\frac{v}{2} .

The value of

T

is close to:

EASY

Physical and Earth Science>Relationships>Waves and Sound>Basic Terms in Wave Motion

The figure below shows pressure variation in two different sound waves in air with time at a given position. Both the figures are drawn to the same scale.

Question Image

Which of the following statement is true?