SCIENCE GRADE 9th

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/seconds

• (c) meter

• (d) unitless

If the speed of sound in water is 1500 m/s, then what is the depth of the sea?

• 3500 m

• 15000 m

• 3000 m

• 15000 m

Tags

NGSS.MS-PS4-2

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?

• Audible sound

• Infrasound

• Ultrasound

• None of these

Tags

NGSS.MS-LS1-8

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

• Slinky

• Bats

• Tuning fork

• None of these

Tags

NGSS.MS-PS4-1

. 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?

• hertz

• decibel

• second

• meter/second

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NGSS.MS-PS4-1

Given below is the diagram of human ear. Choose the correct labeling of the parts A, B and C.

• ear canal

• ear lobe

• Eustachian tube

• cochlea

The sound can travel in air when:

• There is no moisture in the atmosphere

• Both particles as well as disturbance travel from one place to another

• Disturbance travel from one place to another

• Particles of medium travel from one place to another

_________________produced due to vibration of different object

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NGSS.MS-PS4-1

NGSS.MS-PS4-2

You must have seen the doctor checking the sounds produced in the chest or heartbeat of a patient using a medical instrument called Stethoscope. On what principle does this Stethoscope work?

• Wave motion

• Multiple reflections

• Multiple refractions

• None of these

Tags

NGSS.MS-PS4-2

The outer ear is called ______________