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

How does an amplitude affect the loudness of sound explain it with the help of sound wave diagram?

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 number of vibrations produced by a vibrating body in one second 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?

EASY

Science>Physics>Sound>Characteristics of Sound

The sound from a mosquito is produced when it vibrates its wings at an average rate of

500

vibrations per second. What is the time period of the vibration?

EASY

Science>Physics>Sound>Characteristics of Sound

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

HARD

Science>Physics>Sound>Characteristics of Sound

How does the wave pattern of a loud note differ from a soft note? Draw a diagram.

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