class 08 Sound and Its Reflection: Multiple Choice Questions

Chapter Sound and Reflection of sound        Objective:  Multiple choice Questions

1. A sound wave travels from east to west, in which direction do the particles of air move?

(A) East – west                           (B) North - south

(C) Up and down                         (D) None of these

2. In which medium sound travels faster ?

(A) Solid                                   (B) Liquid

(C) Gas                                      (D) None of these

3. What is the name of short duration wave?

(A) Pulse                                    (B) Frequency

(C) Time period                            (D) Velocity

4. What is the velocity of sound in water at room temperature?

(A) 1500 m/s                             (B) 340 m/s

(C) 1500 km/s                         (D) 330 km/s

5. The unit of quantity on which pitch of the sound depends is :

(A) Hertz                                    (B) metre

(C) metre/second                       (D) second

6. The unit of quantity on which loudness of found depends is :

(A) metre                                   (B) Hertz

(C) metre/second                      (D) Decibel

7. Nature of sound wave is :

(A) transverse                          (B) longitudinal

(C) electromagnetic                   (D) seismic

8. Pitch of high frequency sound is :

(A) high                                     (B) low

(C) zero                                     (D) infinite

9. Voice of a friend is recognized by its :

(A) Pitch                                     (B) quality

(C) Intensity                               (D) velocity

10. S I unit of Intensity of Sound waves is :

(A) watt/m^2                              (B) j/s

(C) w/m                                      (D) kwh

Ans: . 1-A                  2-A                     3-A              4-A                 5-A           6-A      7-B              8-A                 9-B         10-A

Objective:  Fill in the blanks

1. Pitch is the sensation  of the ---------- of an emitted sound.

2. A high pitch sound is called a ------ sound

3. A low pitch sound is called a -----------  sound.

4. Loudness of sound wave is ditectly proportional to -------- amplitude

5. The sound energy transferred per unit area per unit time is called -------- of sound.

6. When a body moves with a speed which is greater than the speed of sound in air, it is said to be traveling at --------------

7. When wound waves traveling in air enter into the medium of water, ------- remains unchanged

8. Sound travels faster as the  ------------ of the medium increases by 0.61 m/s with every 1 deg C    9. -----is an apparatus which is used to find the depth of a sea or to locate the under water things.

10. A sound wave of single frequency is called ---------

Ans: 1. Frequency  6. supersonic speed 2. shrill 7. Frequency 3. hoarse 8. temperature 4. Square 9. Sonar 5. intensity 10.Tone