The electron in the hydrogen atom is moving with a speed of 2 . 3 × 10 6 m s - 1 in an orbit of 0 . 53 A 0 . Calculate the period of revolution of electron. π = 3 . 142

Given : Speed of the electron in the hydrogen atom, v = 2 . 3 × 10 6 m s - 1 . The radius of the orbit, r = 0 . 53 A 0 = 0 . 53 × 10 - 10 m . The period of revolution of the electron, T = 2 π r v = 2 × 3 . 142 × 0 . 53 × 10 - 10 2 . 3 × 10 6 = 1 . 44 × 10 - 16 s .

Match the correct answer: a. Amplitude (i) shallow sound b. Lion's roar (ii) number of vibrations per second c. Frequency (iii) maximum displacement d. Chirping of birds (iv) shrill sound

a. Amplitude- (iii) maximum displacement The amplitude of a sound wave is the maximum displacement from the mean position. It is the displacement from the mean position to the extreme position. b. Lion's roar- (i) shallow sound Lion's roar is a shallow sound. The shallow sound is a low pitch sound. c. Frequency- (ii) number of vibrations per second Frequency is the number of vibrations per second. It is the reciprocal of the time period, its unit is Hertz. d. Chirping of birds- (iv) shrill sound The chirping of birds is a shrill sound. The shrill sound is a high pitch sound. a. Amplitude (iii) maximum displacement b. Lion's roar (i) shallow sound c. Frequency (ii) number of vibrations per second d. Chirping of birds (iv) shrill sound

EASY

Earn 100

Explain the factors that affect the loudness of sound with examples ?

Important Questions on Sound

EASY

Science>Physics>Sound>Characteristics of Sound

The electron in the hydrogen atom is moving with a speed of

2.3 \times 10^{6} m s^{- 1}

in an orbit of

0.53 \overset{0}{A}

. Calculate the period of revolution of electron.

(π = 3.142)

HARD

Science>Physics>Sound>Characteristics of Sound

Explain the mechanism of formation of a longitudinal wave when source vibrates in air.

EASY

Science>Physics>Sound>Characteristics of Sound

The maximum displacement of a vibrating body from its mean position is called:

EASY

Science>Physics>Sound>Characteristics of Sound

Define the term time period.

EASY

Science>Physics>Sound>Characteristics of Sound

What is the meant by time period?

MEDIUM

Science>Physics>Sound>Characteristics of Sound

A pendulum oscillates

40

times in

4

seconds. Find its time period and frequency.

EASY

Science>Physics>Sound>Characteristics of Sound

The number of vibrations produced by a vibrating body in one second is called:

MEDIUM

Science>Physics>Sound>Characteristics of Sound

State three factors on which loudness of sound heard by a listener depends.

MEDIUM

Science>Physics>Sound>Characteristics of Sound

Why is the loudness of sound heard by a plucked wire increased when mounted on a soundboard?

EASY

Science>Physics>Sound>Characteristics of Sound

Define the term frequency.

MEDIUM

Science>Physics>Sound>Characteristics of Sound

Match the correct answer:

a. Amplitude	(i) shallow sound
b. Lion's roar	(ii) number of vibrations per second
c. Frequency	(iii) maximum displacement
d. Chirping of birds	(iv) shrill sound