Physics Module Waves

Physics Module ² Waves (by nick SMSHS)

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6.1 UNDERSTANDING WAVES

1.

Two types of waves : i. Transverse wave ii. Longitudinal Longitudi nal waves

A. Transverse wave

(i)

Transverse wave is a wave in which the vibration of particles in the medium is at perpendicular to the direction of propagation of the wave.

A

A

B

B A = crest B = trough (ii).

Example of transverse transvers e wave: i. ««««««««««««««« ii«««««««««««««««« iii««««««««««««««« «

B. Longitudinal waves

(i)

A longitudinal longitudina l is a wave in which the vibration of particles in the medium is parallel to the direction of propagation of wave.

P

P

Q

Q

P = compression Q = rarefaction rarefaction (ii)

Example of longitudinal wave : ««««««««««.. Æ

A wave front is a line or plane on which the vibration of every points on it are in phase and are at the same position/distance from the source of the water.

Æ

Two types of wavefront: (from the top view) i) Circular wavefront

dipper

ii)

plane wavefront


3

Amplitude, Period and Frequency of a Wave

A

C

A

B

B C

the position of the object where is no resultant force acts on the object. 1. Equilibrium Equilibrium position is «««««««««««««««««««««««.

A-B-C-B-A 2. One complete oscillation of the pendulum occurs when the pendulum bob moves from «« the time taken to complete an oscillation 3. The period, T of a vibrating system is «««««««««««««««««... 4.

the number number of com com lete oscil oscillati lations ons Frequency, f is ««««««««««««««««« 1

f =

T

Hertz (Hz) The S.I. unit is «««««..

n

or

f =

t

freeze waves patterns on the screen 5. Stroboscope is use to ««««««««««««««.. rotatio n frequency frequenc y of stroboscope stroboscop e or Stroboscope frequency = number of slits x rotation v = f P

6. Wave speed ,

P

= wavelength of the wave

Exercise 6.1

0

0

Figure 6.10 7.

(a) (b)

The wavelength of the wave in the diagram above is P The amplitude amplitude of the wave wave in the diagram above is A

8.

Indicate the interval which represents one full wavelength. Answer: ««««««««

Figure 6.11

f = np


4

Exercise 6.11

1.

2.

In an experiment , Lim observes that a simple pendulum completes 30 oscillations in 15.0 seconds. What is (a) the frequency of oscillation? (b) the period of oscillation? (a) f = 30/15 = 2 Hz Calculate the frequency of the given wave below

Displacement/cm

5 0

3.

2

4

6

Time/s . -5 : T = 4s Answer f = Hz Based in the displacement-distance displacement-dist ance graph of a wave, find (a) the amplitude (b) the wavelength of the wave wave = 0.25 Hz Displacement/cm

5 -5

2

4

6 Distance/cm

0

4.

A transverse wave is found to have a distance of 4 cm from a trough to a crest, a frequency of 12 Hz, and a distance of 5 cm from a crest to the nearest trough. Determine the amplitude, period, wavelength and speed of such a wave.

5.

A girl moves a long slinky spring at a frequency of 3 Hz to produce a transverse wave with a wavelength of 0.5 m. What What is the wave wave speed of the waves waves along the slinky spring?

6.

The figure shows a wavefront pattern in a ripple tank produced by a vibrating dipper at frequency of 5 Hz. What is the wave speed?

7.

The figure shows a wavefront pattern in a ripple tank produced by a vibrating dipper at frequency of 5 Hz. What is the wave speed?

6.0 cm

4.5 cm

Physics Module ² Waves (by nick SMSHS) 7.5 8. A mechanical stroboscope stroboscop e has 12 slits and rotates at a frequency 5 Hz. The stroboscope is used to observe water waves. The observer notes there are 6 successive bright bands at a distance 20 cm. Calculate the speed of the water waves. 9.

5

20 cm(5 cm (5P)

The figure shows a loudspeaker produces a sound with a frequency 300 (a) the wavelength. (b) the speed of sound

Hz.

Calculate

10.

A given wave travels at a speed of 2 x 10 5 ms-1. If the frequency of the wave is 1000 Calculate the wavelength

11.

(a)

(b)

Base on the figure determine, (i) the amplitude (ii) the wave length -1 What is the frequency of the sound if the speed of sound is 330 ms

200 m

Answer: (a) (i) 2 cm (ii) 50 cm (b) f = v / P = 330 / 0.5 = 660 Hz

Hz,

==


6

Damping

Figure 6.12 1.

Damping is a ««««««««««««««««««««««««««««..

2.

When a system is is damped , the amplitude amplitud e of the of oscillation oscillation decreases slowly until the system stops oscillating.

3.

Damping is usually caused by :(i) external friction frictional al forces such as air resistance (ii) internal forces , where energy is lost from the system in form of heat . heat .

Resonans

A resonance is ««««««««««««««««««««««««««««««««« «««««««««««««««««««««««««««««««««««««««..

Experiment to show a phenomenon pheno menon of resonance

E A B

D C

Figure 6.12: Barton¶s pendulum Pendulum B and D are the same length. When pendulum B oscillates, all the pendulum start to oscillate. But pendulum B and D have the same length, so there have same natural frequency. So pendulum D will oscillates with maximum amplitude.

Physics Module ² Waves (by nick SMSHS) 6.2

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ANALYSING REFRLECTION OF WAVES

1.

R eflection eflection

of a wave occurs when a wave strikes an obstacle such as barrier, plane reflector, mirror and wall.

2.

The reflection of waves obeys the law of reflection : (i) The angle of incidence is equal to the angle of reflection . «««««««««««««««««««««««« (ii)The incident wave, the reflected wave and the normal lie in the same plane . ««««««««««««««««««««««««..

Exercise 6.2

Complete the diagram below.

Reflection of water waves

1.

Show the pattern of the reflection of the water waves waves (a)

(b)

(b)

2.

Show the dark and bright pattern on the screen below.

Water waves Ripple tank

Screen


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Reflection of Light Wave

1. 2.

When rays of light strike any surface the rays are reflected , unless the surface is black, when they are absorbed. A plane mirror is a flat smooth surface which reflects regularly most of the light falling on it.

Figure 6.20 3.

The characteristics characterist ics of reflection reflecti on of light waves: «««««««««««««««««««««««««

4.

The bright and dark bands of the wave pattern formed on the screen because the surface of water acts as lenses. The crest of water waves similar with convex lens and the trough of water waves similar with concave lens.

Exercise 6.21

The diagram shows a single ray of light being directed at a plane mirror. What are the angles of incidence and reflection? (a) (b)

o 35

(b)

Physics Module ² Waves (by nick SMSHS) Reflection of sound waves

1.

The sound waves waves is reflected by walls walls and ceilings of buildings, unborn baby or sea bed.

Figure 6.21 2.

The sound wave from the stopwatch experience a reflection after striking the smooth wall. The angle of incidence, i is equal the angle of reflection, r .

Exercise 6.22

1.

The diagram shows a student shouting in front of a school building. Calculate the time taken by the student to hear the echo of his voice. [The speed of sound in air is 3 40 m s-1 ]

2.

If an echo is heard one second after the holler and reflects off canyon walls which are a distance of 170 meters away, then what is the speed of the wave?

9


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6.3 ANALYSING REFRACTION OF WAVES

1.

The refraction refra ction of water waves occur when there is a «««««««««««««««

2.

frequency but a different After refraction, the wave has the same «««««« speed, wavelength and direction. ««««««««««««««

Refraction of Water Waves

Deep

shallow Figure 6.31

1. When the water water wave travel from a deep area, the direction of the waves waves is refracted ««« (towards/away from) the normal. 2. The angle of incidence, i of the water is ««««.. ( greater / smaller) than the angle of refraction, r 3. When the refraction of a wave happened , the frequency, f does not not change but the ««««««............................................................................... of the wave change. Exercise 6.3

On each of the following diagram, draw the refracted wave by the persp perspex. ex. (a)

(b)


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(c)

(d)

(e)

(f)

Refraction of water wave of the sea water

1.

Why are the speed and wavelength of waves in the middle of the sea almost uniform? unifor m? «««««««««««««««««««««««««««««««««

2.

What do you think would happen to the wave speed if the depth of water is increased? «««««««««««««««««««««««««««««««««

. 3.

Why do the distances between the wavefronts decrease as the waves approach the beach? «««««««««««««««««««««««««««««««««««

4.

Why is the water in the bay stationary compared to the water at the cape? «««««««««««««««««««««««««««««««««


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Refraction of Light Waves

normal

air glass block

Figure 6.33 1. When a ray propagates from one medium to an optically denser medium, medium, the ray refracts «««««««(towards / away from) from) the normal. 2. The speed of light «««««.(decreases/increases) as it propagates in the glass block, causing it to alter the direction of propagation.

Refraction of Sound Waves

Figure 6.34 (a)

Figure 6.3 4 (b)

1.

Sound waves travel faster in warm air than in ««.. (cold/hot) air.

2.

On a hot day, the hot surface of the Earth causes the layer of air near the surface surfa ce to be «««« (warmer/cooler)

3.

This causes sound waves to be ««««. (reflected/refracted) away from the Earth.

4.

On a cool night, the sound waves travel ««««.( slower/faster ««««.( slower/faster )) in the cooler layer of air near the surface of the Earth than in the upper, warmer air. The waves are refracted towards the Earth. Hence, sound can be heard over a longer distance on a cold «««.(night/day) compared with a hot day. day.


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6.4 ANALYSING DIFFRACTION OF WAVES

1. Diffraction of waves is ««....................................... ««................. ........................................... ........................................... .......................................... .................... 2. The effect of of diffraction is obvious obvious only if (a) the size of the aperture or obstacle is small enough. enough. (b) the wavelength is large enough. 3. Frequency, wavelength wavelength and speed of waves do not change change 4. The amplitude of the waves are change Exercise 6.4 Complete the diagrams below by drawing the wavefronts to show the diffraction of water waves.

(a) (a) Narrow gap 

(c) (c) W ider obstacle

(b) (b) Wider g ider gap > 

(d) (d) Narrow obstacle

From the diagram above, 1. The narrower the gap, the more the waves spread out. 2. When the gap is much wider than the wavelength of the waves, there is little diffraction. diffra ction.

Diffraction of light waves

Figure 6.40 Difraction of light through a single slit


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Brigh Brightt at th t he centre

Figure 6. 41 (a) Narrow slit

1. 2. 1.

Figure 6.1(b) Wide slit

The diffraction of light waves occur when the light waves pass through a small slit or small pin hole. The wider middle bright fringe shows that the light waves diffracted diffra cted after pass through a narrow slit. If the slit becomes wider, diffraction pattern becomes ««««.. (less/more) distinct.

Diffraction of sound waves

Figure 6.42 1. 2. 3.

A listener is requested to stand on the other side of the corner of the wall so that the radio is beyond his vision. The listener is able to hear the sound of the radio although it is behind the wall. t is because the sound of the radio spreads around the corner of the wall due to diffraction diffracti on of sound.

6.5 ANALYSING INTERFERENCE WAVE

1.

Interference Interfer ence is the superposition superpos ition of two waves from two coherent sources meet

2.

Two waves are in coherent if they are of the same «««««««. and «««««««...

3.

There are two types of interference interfer ence : i) ««««««««««««««««« ii) «««««««««««««««««


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Principle of superposition

1. The principle of of superposition superposit ion states that««««««««««««««««««««« ««««««««««««««««««««««««««««««««««««« 2. Constructive interference interfer ence occurs when«««««««««««««««««««.««« ««««««««««««««««««««««««««««««««««««« 3.

Destructive interference occurs when«««««««««««««««««««««« «««««««««««««««««««««««««««««««««««««

4.

(a)

Constructive Constructiv e Interference Interf erence

+ =

Before superposition superpositi on

During superposition superposit ion

Figure 6.50 (a)

+

=

Before superposition

During superposition superpos ition

Figure 6.50 (b) Æ

When the vertical displacemet of two waves are in the same direction as in Figure 6.50 (a) and (b), ««««««««««(constructive/destructive) interference occurs.

(b)

Destructive Interference Interf erence

+

=

Before superposition superpositio n

During superposition superpositi on

Figure 6.51 Æ

If a wave with a positive displacement meets another with a negative negative displacement of the same magnitu magnitude, de, they cancel each each other and the combined amplitude becomes ««««««..


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Inteference of Water Waves

Figure 6.52: Inteference of water waves

1.

At the points of constructive interference, the water moves up and down with a «««« (large/ small) amplitude

2.

The points of constructive constru ctive interferences, interfer ences, is known as «««««. ( nodes/antinodes) The points of destructive interferences is known as «««««« (nodes/antinodes).

Exercise 6.5

B C A

Figure 6.53

1.

Figure 6.53 shows the interference pattern of water by two coherent sources of water waves. (i)

At point A, two crest meet resulting in «««««««««.. interference.

(ii)

At point B, two through meet resulting in ««««««««..interference.

(iii)

At point C, a crest meet a trough resulting in «««««««interference.

Physics Module ² Waves (by nick SMSHS) 2.

Complete the table below. Before superposition superpositio n

3.

During superposition superpositi on

After superposition superpositio n

Categorize each labeled position as being a position where either constructive or destructive interference occurs.

i) Constructive interference: interferenc e: ««««««««.

2.

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ii) Destructive Destr uctive interference: interferenc e: «««««««««

. The diagram shows a full-scale interference pattern of a ripple tank experiment 2 seconds after vibration started. The crests of the water ripples are repsented by the dark lines. (a)

What is represented at P at this instant? «««««««««««««««««««««««««««««««««

(b)

What is the frequency of the vibrator? «««««««««««««««««««««««««««««««««


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Two dot vibrators vibrator s which has a separation of 5.0 cm are placed on a water surface in a ripple tank. The distance between two adjacent antinodes on a screen is 3.0 cm. If the perpendicular distance between the dot vibrators and the screen is 10.0 cm, what is the wavelength of the water waves? Answer:

Inteference of Light Waves

1.

Interference occur when at least two coherent light waves overlap or superpose

2.

The superposition superposit ion of 2 rays produces:

constructive interference (i) ««««««««««««««« 3.

destructive interference. (ii)«««««««««««««

When constructive constru ctive occurs there will be a «««« (bright/dark) (bright/dar k) fringe fring e When destructive occurs there will be a ««««(bright/dark) fringe

4.

The wavelength of monochromatic light can be found by the formula: for mula: a = «««««««««««««««««««.. x = «««««««««««««««««««. D = «««««««««««««««««««.


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Exercise 6.51

1.

In a Young¶s double slit experiment, a light of wavelength 633 nm passes through two slit which are 0.5 mm apart. Vertical fringes are observed on a screen placed 4 m from the slits. (i) Calculate the distance between two adjacent bright fringes. (ii) What will happen to the distance between two adjacent bright fringes if a light of shorter wavelength is used?

14

2.

mm

The wavelength of light can be determined with a double-slit plate. The diagram above shows the pattern of interference fringes obtained in a Young¶s double-slit experiment. The separation distance of the two slit is 0.20 mm and the distance between the screen and the double-slit plate is 4.0 m. Calculate the wavelength of the light used in the experiment. Answer :


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Inteference of Sound Waves

The wavelength of sound wave can be found by the formula: a = «««««««««««««««««««.. x = «««««««««««««««««««. D = «««««««««««««««««««. Exercise 6.52

1.

Two loud speakers placed 2 m apart are connected to an audio signal generator that is adjusted to produce sound waves of frequency 550 Hz. The detection of loud and soft sounds as a person moves along a line is at 4.0 m from the loudspeakers. Calculate the (a) wavelength (b) speed of the sound waves. Answer: = 550 x 0.6 = 33 -1 0ms

Analysing Sound Waves

1. Sound waves are longitudinal wavces which require a medium medium for its propagation.

2. The loudness of the sound is depend depend to the amplitude «««««««

3. The pitch of the sound is depend to the ««««««««««««««««««««««

frequenc

4.

Echo is ««««««««««««««««««««««««««««««««««.


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Application of Sound Waves

1. 2. 3.

Ultrasonic

waves with frequencies above 20 k Hz cannot be heard by human ear. The ultrasonic ruler is used to measure the distance between itself and a target. The depth of sea water can be calculated calculated using the for mula : 2d = v x t

Exercise 6.60

1.

In an expedition to determine the depth of a freshwater lake using an ultrasonic ruler, a pulse of ultrasonic sound is generated and travels to the bottom of the lake and reflected by it. The time taken by the pulse to travel to the bottom of the lake and return to the ruler is 0.35 s. If the speed of sound in freshwater is 1 482 m s-1, calculate the depth of the lake. Answer:

Analysing Electromagnetic Waves

1.

The electric and magnetic field vibrate ««««««««.. (perpendicular/parallel) to each other and to the direction of propagation.

2.

Properties of electromagnetic waves (i) .......................................................................................................................................... (ii) .......................................................................................................................................... (iii) .......................................................................................................................................... (iv) ..........................................................................................................................................

3.

Sources and applications of electromagnetic waves in daily life Type of em wave

R adio adio

waves -1 5 P = 10 - 10 m Microwave -3 -1 P = 10 ± 10 m Infrared -6 -3 P = 10 ± 10 m Visible light -7 P = 10 m Ultraviolet radiation -9 -7 P = 10 ± 10 m X-ray -11 -9 P = 10 ± 10 m Gamma

rays -10 m P = 10 ± 10 -14

Source

Application (a) (a) (a) (a) (a) (a) Radiotherapy (b) Detection of cracks in building ructures (a)


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Exercise 6.70

1.

The diagram below shows the pattern of spectrum electromagnetic. In the boxes provided, write the names of the parts given .

wavelength

Gamm

Xray

a ray

Ultra Violet

Visible light

infrare d

microwa ve

fr equen equency 2.

Table 6.70 shows electromagnetic waves P, Q, Electromagnetic waves P Q R

S

Uses R emote emote

control adar system R adar Photograph Kill cancerous cells Table 6.70

Identify P, Q, R and S Answer: P = Infra-red rays Q = Microwaves

R and

S and their uses


1.

23

What will happen to the total energy of an oscillating system which is oscillating at its natural frequency without damping? A Increases B Decreases C R emains emains constant

2.

The figure shows five pendulums that are hung along the wire M N. The pendulum P is displaced and t hen released.

Which of the pendulums will oscillate with the h ighest amplitude? A B C D 3.

Pendulum W Pendulum X Pendulum Pendu lum Y Pendulum Z

Diagram below shows displacement-distance graph of a loaded spring which is vibrating with a frequency 10 Hz.

What is the velocity of the vibration? vibrat ion? A. D.

-1

60 ms . -1 20 ms .

B. E.

40

-1

ms . -1 10 ms .

C.

-1

30 ms


24

Which graph shows the relationship between frequency, f and f and period, T of T of a wave? A

f

B

f

T

C

f

T

D

f

T

T

5.

The diagram shows the transverse waves with point X. X y

Qy Ry Sy Ty

Where would point X be after half a period? A C 6.

Q S

B D

R

T

Which of the following following is a correct example of a longitudinal longitudinal wave and of a transverse wave ?

A B C D

Longitudinal Wave ay Gamma R ay Sound Light adio R adio

Transverse Wave Light ay Gamma R ay R adio adio Sound


25

The diagram shows a displacement-distance graph of a wave.

What is the amplitude of the wave, in m ? A D 8.

16 40

B E

20 80

C

32

The diagram shows a type of transverse waves. A

D

E

B C

F

Which of the following pair of points of points is the wavelength of the wave? A C 9.

AC BE

B D

BD AF

Diagram shows transverse waves formed by a rope.

What is the wavelength and amplitude of the wave?

A B C D

Wavelength 30 cm 40 cm 40 cm 80 cm

Amplitude 20 cm 10 cm 20 cm 10 cm


10.

26

The Diagram shows a ball floating in a water tank.

Which of the following is the correct co rrect movement of the ball, when the wave passes?

11.

A dipper vibrates produces waves in a ripple tank. What happen if the frequency frequency of the dipper is increased? A. B. C.

12.

The wavelength of the wave decreases The amplitude of the wave increases The speed of the wave increases

Which of the following following will change when water waves pass through a narrow gap? A B C D

Frequency Amplitude Speed Wavelength


27

The diagram shows a displacement- time graph of water waves.

Which of the following is true? A B C D

14.

The period of the water wave to vibrate is 25 s The amplitude of the water wave is 0.4 m The frequency of the water wave is 0.05 Hz The wavelength of the water wave is 20 m

Diagram shows plane water waves travelling to wards an L-shaped barrier in a ripple tank. -shaped barrier L-sh H alangan alangan

Which diagram shows the reflected wave pattern?

A

B

C

D

berbentuk L


15.

28

Diagram shows a boat behind a concrete barrier. Boat

Concrete barrier

When the sea waves approach the barrier, the boat is seen moving up and down. This is because the sea waves undergo A reflection C diffraction 16.

B refraction D interference

Diagram shows plane waves moving towards a slit. slit.

The motion of the waves through t hrough the slit will cause a change in the A B C D

17.

amplitude / amplitud wavelength / panjang / panjang gelombang wave speed / laju gelombang frequency / frekuensi / frekuensi

The diagram shows the wave when it passes through a narrow gap.

Which of the following below can cause cau se angle  to increase A B C D

the width of the gap decreases decreases the wave length decreases the frequency increases water in in the ripple ripple tank is shallower


18.

29

Which pattern shows effect of diffraction ?

A

B

C

D

19.

-1

A wave with a frequency of 12 Hz travels with a velocity 36 c m s . What is the distance between the two consecutive amplitudes of the wave? A B C D E

1.5 cm 3.0 cm 4.5 cm 6.0 cm 7.5 cm


30

The diagram shows a superposition of two waves.

Ly Ky

y

N

y

M

Which of the following positions has the maximum amplitude? amplitude? A B C D 21.

K and N M and N L and N M and K

The diagram shows a longitudinal wave travels with the velocity of 36 cm s-1. Direction of th the wave

10.0

cm

What is the frequency of the wave? A C E 22.

0.5 Hz 3.6 Hz 360.0 Hz

B D

1.8 Hz 180.0 Hz

In a Young¶s Experiment, when when the wave length length of a green light light with with 5.0 x 10 - 7 m is used, the distance distance between consecutive fringes fringes is 0.40 mm. If this experiment is repeated using a X light, the distance between consecutive fringes is 0.48 mm Therefore the wave length of X light is « A B C D E

± 7

2.4 x 10 m ± 7 4.2 x 10 m ± 7 5.0 x 10 m ± 7 6.0 x 10 m ± 7 7.0 x 10 m


23.

31

Diagram shows diagrams of different fringes are formed formed on the screens when three different sources of light X, Y and Z are used in Young¶s double-slit experiment.

X

Y

Z

Which of the following shows the probable pro bable sources of light? X

A B C D 24.

Green

Blue Blue Yellow

Y Yellow Green Yellow Green

Z Blue Yellow Green Blue

The diagram shows a displacement-time graph of two notes S and T. Displacement S

T

Time

Which of the following following statement is true ? A B C D

S S T T

is louder but has a lower pitch. is louder and has a higher pitch. is louder but has a lower pitch. is louder and has a higher pitch.


25.

A trumpet and a flute are played by two students. stu dents. The note from the trumpet is louder and has a lower pitch than t he note from the flute. How do the amplitude and frequency of the sound from the trumpet compare to the amplitude and frequency from fro m the flute? trumpet¶s amplitude A B C D

26.

32

larger larger smaller smaller

trumpet¶s frequency higher lower higher lower

The diagram shows a spherical dipper is is vibrating on the water surface of a tilted water tank Sph Spherical dipper

Y

X

Water tank Wooden block

Which of the following wave patterns patt erns will be observed in the water tank? t ank? A X

Y

B X

Y

C X

Y

D X

Y

Physics Module ² Waves (by nick SMSHS) 27

33

Diagram shows water waves moving towards a narrow gap. Deep reg region dalam

K awasan awasan

Shallow reg region K awasan awasan cetek

What are the phenomena that occur when the water waves pass through the gap into the shallow region? efraction R efraction

and diffraction / P embiasan embiasan dan pembelauan R eflection eflection and refraction / P antulan antulan dan pembiasan R eflection eflection and diffraction / P antulan antulan dan pembelauan

A B C

28.

A girl can hear the voices of two people talking around the corner but she cannot see these people because A B C D

29.

Sound waves are reflected better than light waves. Sound waves are refracted better than light waves. Sound waves are diffracted better than light waves. Sound waves are interfered better than light waves.

Diagram shows a wave moving into shallower shallower water.

The wavelength of the waves is reduced because A B C D

frequency and the speed decrease frequency and the speed increase the frequency increases the speed decreases


34

30.

Water waves travel more slowly as they move from deep to shallow shallow water in a ripple tank. Which diagram shows the t he refraction refraction of o f the waves?

31.

Which diagram correctly shows water traveling through deep water to shallower water?


35

The diagram shows wave fronts that move move towards the beach from the sea. sea. It is observed observed that the sea is calmer at the bay than at the cape.

The phenomenom seen in diagram is interference reflection diffraction refraction

A B C D

33.

adio R adio

waves are received rece ived at a house at the t he bottom of a hill.

The waves reach the house because the hill has caused them to be A B C D

34.

diffracted / dibelau radiated / diradiasi reflected /dipantul /dipantul refracted / dibias A pinhole camera is used to observe a ray of light. Which of the following shows the result?


36

Which of the following pattern formed when water waves pass through a narrow gap or a small obstacle in a ripple tank.

36.

A vibrator produces 20 waves per second. If the frequency of the vibrator is doubled, the wave length of the waves will be ¼ of the original wave length A B ½ of the original wave length 4 times of the original wave length C twice the original wave length D equivalent to the original wave length E

37.

Diagram below shows interference pattern which is obtained from an experiment using monochromatic light. The T he screen is located at 3 m from the double slit, while the double double slit separation is 0.5 mm. mm.

-7

If the wavelength of the monochromatic light is 6.5 x 10 m, what is the value of y? -3 -3 -3 A. 1.3 x 10 m B. 3.9 x 10 m C. 7.8 x 10 m -3 -3 D. 9.75 x 10 m E. 11.7 x 10 m 38.

In an experiment of light interference, the distance between two consecutive bright fringes ,x varies varies with distance between double slit and screen, screen, D. Which of the following graph shows the t he correct relationship between x and D?


37

The diagram shows an inteference pattern of water waves from two coherent coherent sources X

Which of the points, do costructive costructive inteference occur ? A B C D 40.

A, B and C A, B and D A, C and D B, C and D

The diagram shows an interference pattern of two coherent water waves of sources, P and Q. Gambar rajah menunjukkan corak interferens bagi dua sumber gelombang air P , dan Q, P yang koheren. Which of the positions A, B, C or D, does destructive interference occur ? Antara kedudukan A, B , C atau D , yang manakah berlakunya interferens memusnah?

41.

Diagram shows two consecutive photographs of a loudspeaker with a lighted candle in front of it.

The observations on the candle flame show that sound waves are A B C D

transverse waves / gelombang / gelombang melintang longitudinal waves / gelombang / gelombang membujur polarized waves / gelombang / gelombang berkutub electromagnetic waves / gelombang / gelombang elektromagnet


Q

P

42.

T

Area S has X-rays Area P has gamma rays Area Q has micro waves Area T has a high frequency waves

Purple Blue Green R ed ed

The diagram shows a modulated wave transmitted through the aerial. Which of the following statements is true regarding the modulated waves? A B C

45.

S

Which of the following colours have the shortest wavelength ? A B C D

44.

R

P,Q,R ,S,T ,S,T are parts of the electromagnet waves which have been arranged according to the wave length in ascending order. If R is the white light, which of the following statements is true? A B C D

43.

38

The frequency of the radio waves vary according to the audio signals. The amplitude of the radio waves vary according to the audio signals. The frequency of the modulated waves varies according to the frequency of the radio waves.

The diagram shows a block diagram of a radio wave receiver. Receiver aerial Loudspeaker

R

S

T

What do Q, R , S and T represent? R A B C D

Tuning Tuning circuit Tuning Tunin g circuit Detector circuit Detector circuit

S

Amplifier circuit Detector circuit Amplifier circuit Tuning Tuning circuit

T

Detector circuit Amplifier circuit Tuning Tuning circuit Amplifier circuit


46.

A VHF (Very High Frequency) radio station broadcasts at a frequency of 90 MHz. The 8 -1 speed of radio waves is 3 x 10 ms . What is the wavelength of the waves broadcast by the station? ebuah stesen radio radio VHF (Frekuensi (Frekuensi Lampau Tinggi) memancarkan gelombang pada S ebuah 8 -1 90 MHz. Laju Laju gelombang radio adalah 3 x 10 ms . Berapakah panjang gelombang, yang di pancarkan oleh stesen radio itu? A. B. C. D. E.

47.

0.3 m 3.3 m 6.0 m 8.0 m 9.0 m

Azimah shouts infront of a high wall. She hears the echo of her voice -1 1.5 seconds later. The velocity of sound in air is is 340 ms . What is the distance d istance between Azimah and the t he wall? A B C D E

204 m 283 m 340 m 510 m 816 m

39

Physics Module Waves

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