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unit 2 Quiz prep 2

Total questions: 143

Worksheet time: 1hrs 12mins

Name
Class
Date
1.

Sound waves travel through………………….

a)

solids.

b)

liquids.

c)

gases.

d)

solids, liquids and gases

2.

Sound waves do not travel through………………………

a)

water.

b)

air.

c)

vacuum.

d)

wood.

3.

All the following indicate the nature of sound waves except that………….

a)

it's mechanical longitudinal waves.

b)

it propagates as spheres of compressions and rarefactions.

c)

its velocity through air is 430 m/s.

d)

no correct answer.

4.

Before using modern technology in communication, people in desert were putting their ears on the ground to hear horses of their enemies at very far places because....................

a)

sense of hearing is stronger than sense of vision.

b)

the velocity of sound through solids (ground) is greater than that through air.

c)

sound travels faster than light.

d)

sound of horses' feet is very loud.

5.

The sound velocity is measured in………………unit.

a)

Hertz

b)

meter

c)

decibel

d)

meter/second

6.

Sound wave that propagates through air with velocity 330 meter/sec. and of wavelength 0.1 meter, its frequency equals……………��...

a)

330 Kilo Hertz.

b)

3300 Hertz.

c)

33 Kilo Hertz.

d)

330 Hertz.

7.

The voice of Adam differs from that of Sara because they are different in……………

a)

kind.

b)

intensity.

c)

pitch.

d)

kind and intensity

8.

The human ears can often differentiate between the voice of the man and that of the woman, because………………….

a)

the voice of a woman is often high pitch and sharp.

b)

the voice of a woman is often low pitch and sharp.

c)

the voice of a woman is often high pitch and rough.

d)

the voice of a man is often high pitch and sharp.

9.

The sound pitch increases by………………….

a)

the decrease in frequency.

b)

the increase in frequency.

c)

the increase in amplitude.

d)

the increase in the distance between the ear and the sound source.

10.

We can prove that the pitch of sound depends on the frequency of vibration of the sound source by using …………..with knowing the number of cycles (turns) and the number of gear teeth.

a)

a.the resonance box

b)

a stretched string of fixed length

c)

Savart's wheel

d)

the tuning fork

11.

The frequency of the vibrating string……….to its length.

a)

equals

b)

is inversely proportional

c)

is directly proportional

d)

has no direct relation

12.

The sound of frequency 200 Hz is………………than the sound of frequency 100 Hz.

a)

stronger

b)

sharper

c)

weaker

d)

harsher

13.

A student rotates Savart's wheel with different velocities, the velocity which gives more rough sound is……………

a)

20 rotation/sec.

b)

300 rotation/min.

c)

6 rotation/sec.

d)

10 rotation/sec.

14.

The frequency of sound produced from a plate touching a gear of 20 teeth in Savart's wheel when the wheel rotates 300 cycle/minute equals…………….Hz.

a)

300

b)

15

c)

6000

d)

100

15.

As the number of teeth of the gear in Savart's wheel increases, the ………. of the produced sound increases.

a)

amplitude

b)

intensity

c)

frequency

d)

quality

16.

The frequency of the sound produced from Savart's wheel depends on…………….

a)

the speed of rotation of the gear only.

b)

the distance between the gear and you only.

c)

the number of gear's teeth only.

d)

the number of gear's teeth and the speed of rotation of the gear.

17.

The scientific term that expresses the strength and the weakness of sound is………….

a)

the frequency of sound.

b)

the pitch of sound.

c)

the quality of sound.

d)

the intensity of sound.

18.

The intensity of sound weakens as we go away from its source, because……………

a)

I α 1/𝑑

b)

I α d

c)

I α 1/𝑑2

d)

I α d2

19.

The measuring unit of sound intensity is………………….

a)

m/sec.

b)

watt/m2.

c)

decibel.

d)

Hertz.

20.

The resonance box increases the intensity of sound because it………………

a)

decreases the vibrating surface area.

b)

increases the vibrating surface area.

c)

increases the frequency of the produced sound.

d)

decreases the pitch of the produced sound.

21.

Sounds of different musical instruments can be differentiated from each other by……

a)

frequency.

b)

harmonic tones.

c)

fundamental tone.

d)

sound intensity.

22.

The higher the…………., the higher the……….

a)

Frequency; volume.

b)

Frequency; pitch.

c)

Sound; pitch.

d)

Wavelength; decibels.

23.

The human ear can distinguish between sounds that are equal in pitch and intensity if their sources are different because the fundamental tone is accompanied by harmonic tones, which are……………….

a)

higher in intensity and frequency.

b)

lower in intensity and higher in frequency.

c)

lower in intensity and frequency.

d)

higher in intensity and lower in frequency.

24.

Sharp tones have……. frequencies, while harsh tones have……. frequencies.

a)

Low; high.

b)

High; high.

c)

High; low.

d)

Low; high.

25.

Ear plugs made of ………. are used to avoid the hazards of noise in loud places.

a)

plastic

b)

silicon

c)

wood

d)

paper

26.

If the wavelength of a sound wave is decreased, what would happen to the sound made by this wave?

a)

It would have a higher pitch

b)

It would have a lower pitch.

c)

It would get softer.

d)

It would get louder.

27.

……………. waves are non-audible sounds.

a)

Infrasonic

b)

Ultrasonic

c)

Sonic

d)

Infrasonic and Ultrasonic

28.

The dolphin's trainer uses a whistle producing a sound which can be heard by dolphins and cannot be heard by man, the frequency of such sound equals ………. Hertz.

a)

20

b)

2000

c)

1000

d)

25000

29.

A sound wave of frequency 30000 cycle/sec. is called ........…wave.

a)

sonic

b)

infrasonic

c)

ultrasonic

d)

radio

30.

Ultrasonic waves are used in .....…

a)

breaking down kidney and ureter stones.

b)

sterilizing food.

c)

discovering landmines.

d)

All of them

31.

Doctors use waves, which have frequency……to break down kidney and ureter stones.

a)

less than 20 Hz

b)

equal to 20 Hz

c)

more than 20 KHz

32.

……………… colour has the lowest deviation.

a)

Violet

b)

Green

c)

Red

d)

Yellow

33.

If the frequency of red colour is 4x1012 Hz, the frequency of violet colour is ......x1012 Hz.

a)

1.5

b)

3.5

c)

4

d)

7.5

34.

The quanta of……………. colour has the lowest energy.

a)

blue

b)

violet

c)

green

d)

red

35.

Which of the following arrangements is correct concerning the increase of photon energy?

a)

Violet → blue → yellow → red

b)

Red → blue → violet → yellow

c)

Violet → red → blue → yellow

d)

Red → yellow → blue → violet

36.

All the following are among the characteristics of violet colour except……………….

a)

it has the highest frequency of the spectrum colours.

b)

it has the longest wavelength of the spectrum colours.

c)

its photon has the largest energy.

d)

it is the nearest colour to the base of the prism.

37.

The medium which permits most light to pass through is called……… medium.

a)

transparent

b)

translucent

c)

semi-transparent

d)

opaque

38.

Media that we can see objects less clearly through are called………. media

a)

opaque

b)

transparent

c)

translucent

d)

spectrum colours.

39.

……………media don't allow light to pass through.

a)

Transparent

b)

Translucent

c)

Semi-transparent

d)

Opaque

40.

All the following are examples of transparent media except ...........

a)

air.

b)

tissue paper.

c)

glass.

d)

clear water.

41.

Which one from the following does not permit the passage of light through it?

a)

Air.

b)

Clear water.

c)

Flint glass.

d)

Milk.

42.

Light can be easily transmitted through…………..media.

a)

transparent

b)

semi-transparent

c)

opaque

d)

(a) and (b)

43.

The human skin is considered as a /an……. medium.

a)

transparent

b)

opaque

c)

translucent

d)

no correct answer

44.

By increasing the thickness of the transparent medium, the quantity of light that passes through it………………..

a)

decreases.

b)

increases.

c)

remains constant.

45.

Light …………………

a)

travels in straight lines.

b)

consists of compressions and rarefactions.

c)

can be analysed.

d)

travels in straight lines and can be analysed.

46.

The light intensity of a surface is inversely proportional to the ………between the surface and the source of light.

a)

distance

b)

square of the distance

c)

cube of the distance

d)

(a) or (b) is correct.

47.

If the distance between a surface and light source decreases to its half, the light intensity of the surface .........

a)

decreases to its one fourth.

b)

decreases to its half.

c)

increases twice.

d)

increases four times.

48.

Light……… plays an important role in the formation of inverted images of the objects on the road when rain falls.

a)

velocity

b)

refraction

c)

reflection

d)

frequency

49.

In……………reflection, the reflected rays are reflected in many directions.

a)

irregular

b)

uniform

c)

regular

d)

total internal

50.

A regular reflection happens when light rays fall on .......

a)

a woollen jacket.

b)

a stainless-steel sheet.

c)

a leaf of a tree.

d)

a piece of leather.

51.

Light is reflected …… when it falls on a smooth bright surface.

a)

regularly

b)

irregularly

c)

and refracted

d)

and scattered.

52.

Light is reflected ……. when it falls on a rough surface.

a)

regularly

b)

irregularly

c)

and refracted

d)

in one direction

53.

The angle between the reflected ray and the line perpendicular to the reflecting surface at the point of incidence is called the angle of…………………

a)

emergence.

b)

incidence.

c)

refraction.

d)

reflection.

54.

If the angle between the incident light ray and the reflected light ray is 90°, so the angle of incidence equals .......

a)

b)

30°

c)

45°

d)

90°

55.

If the angle between a reflected light ray and a reflecting surface is 30°, so the angle of reflection will be equal to …….

a)

15°

b)

30°

c)

60°

d)

90°

56.

If you know that the incident ray which falls perpendicular on a reflecting surface reflects on itself, so the angle of reflection is equal to……………….

a)

b)

90°

c)

120°

d)

180°

57.

The angle of incidence of light is … its angle of reflection.

a)

larger than

b)

smaller than

c)

equal to

58.

The ability of the transparent medium to refract the light is called the……. of the medium.

a)

refractive index

b)

density

c)

optical density

d)

viscosity

59.

The…………is the change in the direction of light rays when light passes from a transparent medium to another transparent medium of different optical density.

a)

light reflection

b)

light refraction

c)

light absorption

d)

light separation

60.

The angle between the refracted light ray and the normal at the point of incidence on the separating surface is …...

a)

the angle of reflection.

b)

the angle of refraction.

c)

the angle of incidence.

d)

no correct answer.

61.

The angle between the emergent light ray and the normal at the point of emergence on the interface is called the angle of …………………

a)

incidence.

b)

reflection.

c)

refraction.

d)

emergence.

62.

Light refraction is due to the difference in ………… through different media.

a)

sound intensity

b)

nature of the surface

c)

light velocity

d)

all the previous answers

63.

The angle of incidence is greater than the angle of refraction when a light ray travels from……………………

a)

air to glass.

b)

water to air.

64.

When light ray travels from air to water, it ………….

a)

refracts near the normal.

b)

refracts far from the normal.

c)

passes without refraction.

d)

reflects.

65.

The absolute refractive index of any material is always……...

a)

more than one.

b)

less than one.

c)

equal to one.

d)

equal zero.

66.

The absolute refractive index is the ratio between the speed of light through air and

a)

the speed of light through another medium.

b)

the speed of light through the same medium.

c)

the speed of sound through the same medium.

d)

no correct answer.

67.

A pencil seems broken when it is placed in a glass cup of water due to the …of light.

a)

reflection

b)

refraction

c)

separation

68.

Light travels through space at a speed of ……m/s.

a)

3×107

b)

3×106

c)

3×108

d)

No correct answer

69.

The regular reflection occurs on……..surface.

a)

Rough

b)

Smooth

c)

(a) and (b)

d)

No correct answer

70.

Sound travels in air at a velocity …….m/s.

a)

3400

b)

430

c)

340

d)

No correct answer

71.

Sound …………. is a property of sound by which the ear can distinguish between harsh and sharp voices.

a)

Intensity

b)

Quality

c)

Pitch

d)

All the answers are correct.

72.

Two sounds have the same pitch. Which of the following must be the same for the sound waves that transmit these sounds?

a)

Frequency

b)

Amplitude

c)

(a) and (b)

d)

No correct answer

73.

Sound………is the amount of energy falling perpendicular to a unit area surrounding this point in one second.

a)

Intensity

b)

Quality

c)

Pitch

d)

No correct answer

74.

When the distance between the source of light and the surface decreases to third, the light intensity on the surface ....

a)

increases to three times

b)

increases to nine times

c)

decreases to third

d)

decreases to ninth

75.

When the distance between the sound source and the ear is doubled, the sound intensity……………

a)

Decrease to its half.

b)

Increase twice.

c)

Increase four times.

d)

Decrease to its quarter.

76.

Sound velocity through air may be……………….

a)

330 m/sec. only.

b)

340 m/sec. only.

c)

350 m/sec. only.

d)

All the previous answers.

77.

If a sound frequency 3000 vibrations/second is produced, we call its waves are…………… waves.

a)

Sonic.

b)

Ultra sonic.

c)

Infra sonic.

d)

Transverse.

78.

A Savart wheel makes 6 turns in a time of 2 seconds. The wheel has 120 teeth. What is the frequency of the sound produced by the wheel?

a)

240 Hz

b)

122 Hz

c)

1,440 Hz

d)

360 Hz

79.

The media that we can see objects less clearly through them are called ………….

a)

Opaque

b)

Transparent

c)

Translucent

80.

The energy of a yellow photon is …………. The energy of a violet photon.

a)

More than.

b)

Less than.

c)

Equal

d)

All the previous answers.

81.

Sound intensity is…………. proportional to the square of the amplitude of vibration of the source.

a)

Inversely

b)

Not

c)

Directly

82.

We have got the refractive index of 4 materials which result of the four is incorrect……………

a)

0.8

b)

1.3

c)

1.8

d)

1.5

83.

All of the following are factors affecting sound intensity except………..

a)

amplitude of vibration

b)

wind direction

c)

medium density

d)

frequency

84.

A Savart wheel produces a sound. When the pedals are turned faster, the time between teeth hitting the flexible metal sheet……..

a)

increases

b)

decreases

c)

does not change

d)

no correct answer

85.

The sound travelling in air has less intensity than that travelling in carbon dioxide.

a)

Because the density of air is lower than the density of carbon dioxide.

b)

Because the density of air is bigger than the density of carbon dioxide.

c)

Because the density of carbon dioxide is lower than the density of air.

d)

No correct answer.

86.

The human ear can distinguish between sounds through different factors ……………………….

a)

sound intensity

b)

sound pitch

c)

sound quality

d)

all the answers are correct

87.

When a light ray travels from water to air, the angle of ………… is greater than the angle of…………………

a)

Incidence; refraction.

b)

Refraction; incidence.

c)

Incidence; reflection

d)

Reflection; incidence.

88.

If the angle between the incident sound ray and reflecting surface is 40°, the angle of reflection equals………………….

a)

40°

b)

50°

c)

60°

d)

140°

89.

The sound of non-uniform frequency, which is uncomfortable to be heard.

a)

Noise tones

b)

Musical tones

c)

Sound intensity

d)

No correct answer

90.

The intensity of light of a surface decreases to its quarter as the distance between the surface and light source is doubled.

a)

Because light intensity is not proportional to square distance.

b)

Because light intensity is inversely proportional to square distance.

c)

Because light intensity is directly proportional to square distance.

d)

No correct answer.

91.

If the speed of sound through air is 340 m/s and the frequency of vibrating body = 170 Hz, its wavelength equals ...

a)

4 m

b)

3 m

c)

2 m

d)

No correct answer

92.

The wavelength of sound wave is the distance between the centers of two………………….

a)

Compressions only.

b)

Rarefactions only.

c)

Compressions or rarefactions.

d)

No correct answer.

93.

Light waves are…………………waves.

a)

mechanical transverse

b)

electromagnetic transverse

c)

electromagnetic longitudinal

d)

mechanical longitudinal

94.

The inability to see the impurities presence in black honey.

a)

Because it is an opaque medium which absorbs all light.

b)

Because it is an opaque medium which reflects all light.

c)

Because it is an opaque medium which refracts all light.

d)

No correct answer

95.

The sound produced from the school bell is considered …..... Waves.

a)

longitudinal

b)

electromagnetic

c)

transverse

d)

no correct answer

96.

What happens if decreasing the amplitude of the sound source.

a)

Sound intensity decreases.

b)

Sound intensity increases.

c)

Sound intensity changes.

d)

No correct answer.

97.

Sound can be heard from all surrounding directions.

a)

Because air travels through sound as pulses of compression and rarefactions whose centers are the air source.

b)

Because sound travels through air as pulses of compression and reflections whose centers are the sound source.

c)

Because sound travels through air as pulses of compression and rarefactions whose centers are the sound source.

d)

Because sound travels through air as pulses of compression and rarefactions whose centers are the air source.

98.

Calculate the frequency of a tone produced by Savart's Wheel in 100 s, if the no. of rotations multiplied by the number of teeth equals 28800.

a)

2880 Hz

b)

80 Hz

c)

288 Hz

d)

No correct answer

99.

The frequency of the sound wave, which propagates through air in 340 m/s and whose length is 0.1 m, equals ……

a)

3400 Hz.

b)

340.1 Hz

c)

34 Hz

d)

No correct answer

100.

The wavelengths of visible light ranges between ……. Nm.

a)

380 : 700

b)

400 : 600

c)

100 : 500

d)

350 : 800

101.

All the following are factors affecting sound intensity except …………

a)

amplitude

b)

frequency

c)

medium density

d)

wind direction

102.

The main source of light on the earth's surface is the ……

a)

Sun

b)

Star

c)

Moon

d)

Candle

103.

The color ……………. Has the highest frequency among the spectrum colors.

a)

Violet

b)

Green

c)

Red

d)

yellow

104.

White light consists of …… ………. Spectrum colors.

a)

Nine

b)

Eight

c)

Six

d)

seven

105.

Photon energy= plank's constant x ……………….

a)

Photon velocity

b)

Photon frequency

c)

Light intensity

d)

No correct answer

106.

The distance that light travels in second is …………..

a)

Velocity

b)

Intensity

c)

Frequency

107.

Light travels in …………. lines.

a)

Circular

b)

Zigzag

c)

Curved.

d)

Straight

108.

……….. color has the highest wave length.

a)

Red

b)

Violet

c)

Green

d)

yellow

109.

Is the distance which is covered by sound waves in one second.

a)

Sound intensity

b)

Sound intensity at a point

c)

Sound velocity

d)

Sound quality

110.

are sound waves of frequency of less than 20 Hz.

a)

Sonic waves

b)

Ultra sonic waves

c)

Infra sonic waves

d)

No correct answer

111.

Ultrasonic waves are used in several fields such as …..

a)

Military field.

b)

industrial field

c)

medical field

d)

all of the answers are correct

112.

Light shines on a surface. Which of the following properties of light is related to the intensity of the light shining on that surface?.

a)

The color of the light

b)

The speed of the light

c)

The brightness of the light

d)

No correct answer

113.

Which of the following correctly describes the term infrasound?

a)

Sound waves with frequencies lower than 0 Hz

b)

Sound waves that transfer thermal energy

c)

Sound waves with frequencies lower than those that can be heard by humans

d)

No correct answer

114.

Which of the following correctly explains why a person standing a few meters away from an object producing infrasound would not hear the infrasound?

a)

The human ear does not oscillate at infrasonic frequencies.

b)

Infrasound can only travel a few centimeters through air.

c)

Infrasound is too quiet for human hearing.

d)

No correct answer

115.

If the wavelength of a sound wave is increased, what would happen to the sound made by this wave?

a)

It would have a higher pitch

b)

It would have a lower pitch.

c)

It would get softer.

d)

It would get louder.

116.

If the wavelength of a sound wave is decreased, what would happen to the sound made by this wave?.

a)

It would have a higher pitch

b)

It would have a lower pitch.

c)

It would get softer.

d)

It would get louder.

117.

If the amplitude of a sound wave is decreased, what would happen to the sound made by this wave?

a)

It would have a higher pitch

b)

It would have a lower pitch.

c)

It would get softer.

d)

It would get louder.

118.

If the amplitude of a sound wave is increased, what would happen to the sound made by this wave?

a)

It would have a higher pitch.

b)

It would get softer.

c)

It would have a lower pitch.

d)

It would get louder.

119.

As the wavelength of sound increases, the frequency ……

a)

Is higher pitched.

b)

Increases.

c)

Decreases.

d)

Stay the same.

120.

As sound waves travel through air, they cause air molecules to…………

a)

Bend.

b)

Lose energy.

c)

Be absorbed.

d)

Vibrate.

121.

The higher the…………., the higher the……….

a)

Frequency; volume.

b)

Frequency; pitch.

c)

Sound; pitch.

d)

Wavelength; decibels.

122.

When the distance between the sound source and the ear is doubled, the sound intensity…………..

a)

Decreases to its half.

b)

Increases twice.

c)

Increases four times.

d)

Decreases to its quarter.

123.

Piano's sound differs from that of violin even they have the same intensity and pitch.

a)

Because they are different sources.

b)

Because they are equal in pitch only.

c)

Due to the difference in their harmonic tones.

d)

All the answers are correct.

124.

The angle between the emergent light ray and the normal at point of emergence on the interface is called angle of ……..

a)

Refraction.

b)

Deviation.

c)

Emergence

d)

Incidence.

125.

The intensity of sound is directly proportional to………

a)

The square of the distance from the distance from the source.

b)

The square of the amplitude.

c)

The distance from the source to the ear.

d)

No correct answer.

126.

Sharp tones have……. Frequencies, while harsh tones have…..frequencies.

a)

Low; high.

b)

High; high.

c)

High; low.

d)

Low; high.

127.

We see the sunlight, but don't hear the explosions that occur on the surface of the sun.

a)

Because light travels in vacuum while sound needs a medium to propagate through.

b)

Because light travels in medium while sound needs a vacuum to propagate through.

c)

Because the sun is very far.

d)

Because sound is faster than light.

128.

The light ray which falls perpendicular to a reflecting surface , reflects on itself.

a)

Because it refracts.

b)

Because angle of incidence equal angle of reflection equal zero.

c)

Because angle of incidence larger than angle of reflection

d)

No correct answer.

129.

If the angle between the incident light ray and the reflected light ray is 600, so the angle of reflection equals .....

a)

15o

b)

30o

c)

90o

d)

120o

130.

The human ear can hear sounds of frequency ………

a)

50 KHz

b)

30 KHz

c)

300 Hz

d)

10 Hz

131.

Sound travels in straight lines in all directions away from a sound source. How many times greater is the sound intensity at a distance of 1 meter away from the sound source than at a distance of 2 meters away from the sound source?

a)

4 times

b)

3 times

c)

2 times

d)

1 time

132.

When the distance between the source of light and the surface of a wall decreases , the light intensity on a surface ....

a)

Decreases

b)

Increases

c)

Is doubled

d)

Remains constant.

133.

If the angle between the incident and the reflected rays is 400, so the angle of reflection = …………….

a)

90o

b)

80o

c)

40o

d)

20o

134.

As the velocity of the rotation of the gear in savart's wheel decreases, the frequency decreases, consequently the…….of the sound decreases.

a)

Pitch.

b)

Type.

c)

Amplitude.

d)

Intensity.

135.

If a sound of frequency 3000 vibrations/seconds is produced, we call its waves are……………..

a)

Sonic

b)

Ultra sonic

c)

Infrasonic

d)

Transverse

136.

The level of sound intensity (or noise intensity) is measured by………….

a)

Watt.

b)

Decibel.

c)

Meters.

d)

No correct answer.

137.

They are sound waves of frequencies lower than 20 Hz.

a)

Ultrasonic waves.

b)

Infrasonic waves.

c)

Sonic.

d)

No correct answer.

138.

Sound intensity is directly proportional to the …………

a)

Amplitude

b)

square of amplitude

c)

(a) and (b)

d)

No correct answer

139.

The tones accompanying the fundamental tone, but they are higher in pitch and less in intensity.

a)

Harmonic tones.

b)

Noises.

c)

(a) and (b)

d)

No correct answer

140.

The wood does not allow the passage of light through it.

a)

Because it is an opaque medium that reflects all light.

b)

Because it is an opaque medium that absorbs all light.

c)

Because it is an opaque medium that refracts all light.

d)

No correct answer.

141.

Light waves are considered electromagnetic waves.

a)

Because they need a medium to travel through.

b)

Because they do not need a medium to travel through.

c)

They are not electromagnetic waves.

d)

No correct answer.

142.

The medium which does not permit light to pass through it.

a)

Opaque medium.

b)

Spectrum colors.

c)

Translucent media.

d)

Transparent media.

143.

A structure used in the analysis of light.

a)

Periscope.

b)

Savart's wheel

c)

Triangular glass prism

d)

No correct answer.