General Science #41 Multiple Choice Questions (MCQ) : Assam Jobs Guide

GENERAL SCIENCE #41

MULTIPLE CHOICE QUESTIONS

1. Note is a sound ……………

(a) of mixture of several frequencies

(b) of mixture of two frequencies only

(c) of a single frequency

(d) always unpleasant to listen

Answer: (c)

2. A key of a mechanical piano struck gently and then struck again but mush harder this time. In the second case ……………

(a) sound will be louder but pitch will not be different

(b) sound will be louder and pitch will also be higher

(c) sound will be louder but pitch will be lower

(d) both loudness and pitch will remain unaffected

Answer: (a)

3. In SONAR, we use ……………

(a) ultrasonic waves

(b) infrasonic waves

(c) radio waves

(d) audible sound waves

Answer: (c)

4. Sound travels in air if ……………

(а) particles of medium travel from one place to another

(b) there is no moisture in the atmosphere

(c) disturbance moves

(d) both particles as well as disturbance travel from one place to another

Answer: (d)

5. When we change feeble sound to loud sound we increase its ……………

(a) frequency

(b) amplitude

(c) velocity

(d) wavelength

Answer: (b)

6. Which kind of sound earthquake produces before the main shock wave begins?

(a) Ultrasound

(b) Infrasound

(c) Audible sound

(d) None of the above

Answer: (a)

7. Infrasound can be heard by which of the following?

(a) Dog

(b) Bat

(c) Rhinoceros

(d) Human beings

Answer: (c)

8. Before playing the orchestra in a musical concert, a sitarist tries to adjust the tension and pluck the string suitably. By doing so, he is adjusting ……………

(a) intensity of sound only

(b) amplitude of sound only

(c) frequency of the sitar string with the frequency of other musical instruments

(d) loudness of sound

Answer: (c)

9. The sound can travel in air when ……………

(a) Particles of medium travel from one place to another

(b) There is no moisture in the atmosphere

(c) Disturbance travel from one place to another

(d) Both particles as well as disturbance travel from one place to another

Answer: (c)

10. We can distinguish between a man’s voice and a woman’s voice of the same loudness even without seeing them. This is due to a characteristic of sound which measures the shrillness of sounds. Can you choose the correct unit of the quantity on which this characteristic of sound depends?

(a) Hertz

(b) Meter/second

(c) Meter

(d) Unitless

Answer: (a)

11. A key of mechanical piano is first struck gently and then struck again but much harder this time. What kind of change in sound will you observe in the second case?

(a) Sound will be louder but the pitch will not be different

(b) Sound will be louder and the pitch will also be higher

(c) Sound will be louder but the pitch will be lower

(d) Both loudness and pitch will remain unaffected

Answer: (c)

12. The echo-receiver of a sonar attached to a ship, receives the echo from the bottom of sea 4 seconds after the ultrasonic waves were sent into the sea. If the speed of sound in water is 1500 m/s, then what is the depth of the sea?

(a) 6000 m

(b) 3000 m

(c) 15000 m

(d) 3500 m

Answer: (b)

13. Before the main shock waves, the earthquake produces the characteristic sound waves which some animals like rhinoceros can hear. Can you guess the kind of sound waves produced here?

(a) Infrasonic sounds

(b) Ultrasonic sounds

(c) Audible Sounds

(d) None of these

Answer: (a)

14. On increasing the temperature, the speed of sound in air ……………

(a) increases

(b) decreases

(c) does not change

(c) first increases then becomes constant

Answer: (a)

15. Loudness measures the sound energy reaching the ear per second and depends on the amplitude of the sound wave. What is the unit used to measure the loudness of sound?

(a) Hertz

(b) Decibel

(c) Meter/second

(d) Second

Answer: (b)

16. We can easily distinguish between the sounds of the different singers even without having seen them. This is all due the different quality or timber of their sounds. On what factor does the quality of sound depend?

(a) Wavelength

(b) Waveform

(c) Wave frequency

(d) Wave amplitude

Answer: (b)

17. The bats can fly in the darkness of night without colliding with the other objects by emitting special sounds while flying. Which characteristic of sound is used by the bats to navigate?

(a) Ultrasound

(b) Infrasound

(c) Audible sound

(d) None of the above

Answer: (a)

18. The sound travels from particle to particle in the form of vibrations and has different speeds in different mediums. The maximum speed of vibrations which produce audible sound will be in ……………

(a) Sea water

(b) Ground glass

(c) Human blood

(d) Dry air

Answer: (b)

19. Which of the following can produce longitudinal as well as transverse waves under different conditions?

(a) Bats

(b) Slinky

(c) Tuning fork

(d) None of the above

Answer: (b)

20. If the speed of a wave is 380 m/s and its frequency is 1900 Hz, then what will be the wavelength of the wave?

(a) 20 m

(b) 0.2 m

(c) 200 m

(d) 2 m

Answer: (b)