Practice Questions with Answers - Multiple Choice Questions

MCQ Questions for Class 9 Science Chapter 12 Sound

MCQ Questions for Class 9 Science Chapter 12 Sound

 

Multiple Choice Questions

Question 1.
For hearing a distinct sound, the time interval between the original sound and the reflected one must be at least:
(a) 1 s
(b) 0.1 s
(c) 2 s
(d) 0.2 s

Answer

Answer: (b) 0.1 s


Question 2.
The persistence of sound in an auditorium is the result of repeated reflections of sound and is called:
(a) reverberation
(b) audible
(c) distinct sound
(d) reflection

Answer

Answer: (a) reverberation


Question 3.
The speed v, frequency υ, and wavelength λ, of sound are related by the equation:
(a) v = λυ
(b) υ = λv
(c) λ = υv
(d) v = \(\frac{\lambda}{υ}\)

Answer

Answer: (a) v = λυ


Question 4.
The speed of sound is maximum in:
(a) solids
(b) liquids
(c) gases
(d) All of these

Answer

Answer: (a) solids


Question 5.
Our ears are sensitive to sound frequencies between:
(a) 20 Hz to 20 kHz
(b) 2 Hz to 20 Hz
(c) 20 kHz to 200 kHz
(d) 2000 kHz to 20000 kHz

Answer

Answer: (a) 20 Hz to 20 kHz


Question 6.
Which of the following waves are produced by bats?
(a) Infrasonic waves
(b) Ultrasonic waves
(c) Audible waves
(d) All of these

Answer

Answer: (b) Ultrasonic waves


Question 7.
Maximum tolerable sound is:
(a) 0 dB
(b) 10 dB
(c) 60 dB
(d) 120 dB

Answer

Answer: (d) 120 dB


Question 8.
Sound waves are:
(a) magnetic waves
(b) electric waves
(c) electromagnetic waves
(d) mechanical waves

Answer

Answer: (d) mechanical waves


Question 9.
In SONAR, we use:
(a) ultrasonic waves
(b) infrasonic waves
(c) radio waves
(d) audible sound waves

Answer

Answer: (a) ultrasonic waves


Question 10.
Sound travels in the air if:
(a) particles of medium travel from one place to another
(b) there is no mixture in the atmosphere
(c) disturbance moves
(d) both particles as well as disturbance travel from one place to another

Answer

Answer: (c) disturbance moves