When a sound wave travels through air, the air particles
a) vibrate along the direction of the wave motion
Velocity of sound in a gaseous medium is 330 m s1. 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 m s^-1
The frequency, which is audible to the human ear is
b) 20 kHz
The velocity of sound in air at a particular temperature is 330 m s1. What will be its value when temperature is doubled and the pressure is halved?
c) 330 × √2 m s^–1
If a sound wave travels with a frequency of 1.25 104 Hz at 344 m s1, the wavelength will be
c) 0.02752 m
The sound waves are reflected from an obstacle into the same medium from which they were incident. Which of the following changes?
d) none of these
Velocity of sound in the atmosphere of a planet is 500 m s1. The minimum distance between the sources of sound and the obstacle to hear the echo, should be
c) 25 m
Rapid back and forth motion of a particle about its mean position is called _____
Vibration
If the energy in a longitudinal wave travels from south to north, the particles of the medium would be vibrating in _____
both north and south
A whistle giving out a sound of frequency 450 Hz, approaches a stationary observer at a speed of 33 m s^-1. The frequency heard by the observer is (speed of sound = 330 m s^-1) ______.
500 Hz
A source of sound is travelling with a velocity 40 km/h towards an observer and emits a sound of frequency 2000 Hz. If the velocity of sound is 1220 km/h, then the apparent frequency heard by the observer is ___________.
2068 Hz
Infrasonic
10 Hz
Echo
Ultrasonography
Ultrasonic
22 kHz
High pressure region
Compressions
Sound can travel through solids, gases, liquids and even vacuum.
FALSE (Sound waves cannot travel through vacuum)
Waves created by Earth Quake are Infrasonic.
TRUE
The velocity of sound is independent of temperature.
FALSE (The velocity of sound is independent of gas pressure)
The Velocity of sound is high in gases than liquids.
FALSE (The Velocity of sound is high in liquids than gases because gases are least elastic)
(A): Assertion: The change in air pressure affects the speed of sound... (R): Reason: The speed of sound in a gas is proportional to the square of the pressure
(d) Assertion is false, but the reason is true.
(A): Assertion: Sound travels faster in solids than in gases... (R): Reason: Solid posses a greater density than that of gases.
(b) Both the assertion and the reason are true, but the reason is not the correct explanation of the assertion.