Part One: Multiple Choice Questions (2 marks each, total 50 marks)
1. Which of the following is a light source? (
)
A. A bright moon in the night’s sky
B. Fireflies in the dusk
C. Sparkling jewels
D. Glistening water droplets in sunlight
2. Which of the following statements about ultraviolet light is incorrect? (
)
A. It causes some phosphor coating to glow
B. It causes human skin to tan
C. It is produced by the Sun
D. It travels faster than light
3. As shown in the picture, punch a hole in the bottom of an empty can, then cover the other end with tracing paper. Face
the hole to a candle flame, you will see an image of the flame on the tracing paper. This is an effect of (
)
A. light travelling in straight lines
B. reflection of light
C. refraction of light
D. dispersion of light
4. Regarding propagation of light, which of the following statements is correct? (
)
A. Light travels in straight lines in air only
B. Light travels in straight lines under any circumstances
C. Light does not travel straight in glass
D. Light travels in straight lines in the same uniform medium
5. Which of the following is attractive to some insects like mosquitoes and flies? (
)
A. Red light
B. Purple light
C. Infrared radiation
D. Ultraviolet radiation
6. Sunlight goes through a prism and is dispersed into rainbow colored lights. This shows (
)
A. sunlight is a compound light
B. Prism contains colored lights
C. Prism changes the color of sunlight
D. Prism changes monochromatic light into multi-colored lights
7. In a pinhole imaging experiment, a student uses a few cards each with a hole of different shape but the holes are of
roughly the same size to observe the sun spots on the ground. Which aspect of the experiment is she studying in relation
to the image formed on the ground? (
)
A. The shape of the sun spot
B. The size of the sun spot
C. The shape of the pinhole
D. The size of the pinhole
8. Regard the rainbow in the sky, which of the following statements is incorrect? (
)
A. The rainbow must be arched
B. The outside of the arch is red and the inside is violet
C. The outside of the arch is violet and the inside is red
D. Rainbow usually is seen right after a rainfall
9. In the hot summer people usually like to stay in the shade of a tree. The formation of shade is due to the effect of ( )
A. light travelling in straight lines
B. reflection of light
C. Refraction of light
D. dispersion of light
10. People usually wear light colored clothing in summer, especially white. This is because (
)
A. Light colors or white are more noticeable
B. White color is pretty
C. White color absorbs all visible light
D. White color reflects all visible light
11. As shown below, two balloons of the same size and material, one white and one black, are inflated with hydrogen gas,
and then exposed in hot sunlight for 10 minutes (balloons do not burst), one will find (
)
A. The white balloon is larger in size
B. The black balloon is larger in size
C. They are the same size
D. Their relative sizes cannot be determined.
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12. The sun’s rays reaching our Earth are almost parallel. This is because (
)
A. The sun is very big and emits parallel light rays B. The sun is very far away and much, much larger than Earth
C. The sun is close to Earth and Earth is bigger
D. Sunlight is refracted when reaching Earth and becomes parallel
13. Which of the following statements about light and color is correct? (
)
A. White light is monochromatic
B. A red flag is red because it absorbs red light and reflects other colored lights
C. We see images on a projector screen because the screen is a light source
D. An infrared oven uses the heating effect of infrared radiation
14. We often see and use automatic water taps and hand driers. We need only put our hands under the tap or drier,
water or hot air will come out. Which radiation does out body emit that causes these machines to start working? ( )
A. Ultraviolet rays
B. Visible light
C. Infrared rays
D. None of the above
15. Which of the following light is monochromatic? (
)
A. Incandescent light
B. Green light
C. Candle light
D. Sunlight
16. Which of the following phenomena is an effect of light travelling in straight lines? (
)
A. Egg looks bigger in a glass of water
B. the reflection of a bird
C. The fish looks shallower than it actually is in water
D. Making shadow puppets with hands
17. The lower case letter “b” will produce a pinhole image of (
)
A. “b”
B. “p”
C. “d”
D. “q”
18. We often see on TV or in a movie that a flying airplane viewed from behind often looks shimmering or shaking. Which
of the following is a correct explanation? (
)
A. The plane blasts out hot air that causes air density to be uneven, and light does not travel straight in such
___medium
B. The plane itself is shaking when taking off
C. The video camera is shaking
D. The plane is travelling too fast
19. China successfully launched a weather satellite. It is a geostationary satellite that hovers direct above the equator at
the longitude of 105°E. It sends infrared cloud images back to earth that shows different temperatures of the cloud
by different shades of gray in the picture. The onboard infrared sensor achieves this by using the ______ of the infrared
radiation? (
)
A. invisibility
B. penetrating quality
C. heating effect
D. chemical effect
20. Which of the following statements is correct? (
)
A. Plants grow by using the invisible portions of the sun’s radiation energy
B. Plants’ leaves are green, and this is because the chlorophyll in the leaves only absorbs green light of the sun
C. When plants make chlorophyll they absorb red and green lights of the sun
D. The infrared radiation of the sun raises the plants’ temperature and drives their transpiration making plants grow --faster
21. Which of the following phenomena cannot be explained by the fact that light travels in straight lines? ( )
A. The surface of a calm lake reflects nearby mountains
B. The occurrence of solar eclipse and lunar eclipse
C. Formation of shadows
D. When shooting a rifle, one should line up one’s dominant eye, the rear sight, the front sight and the target
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22. In the Warring Periods of ancient China, the famous educationist Mozi studied the phenomenon of pinhole imaging. As
shown in the picture, he drilled a tiny hole in a thin panel of wood and saw that a candle flame formed an inverted
image on the wall. Which of the following is correct? (
)
A. Pinhole imaging shows that light travels in straight lines
B. The pinhole must be round
C. When keeping the distance between the candle and the wall
----the same, moving the wood panel toward the wall would make
---- the image bigger
D. The image on the wall is a virtual image
23. A beam of light is shone on a piece of paper, and the paper appears green, that means (
)
A. the light is green, the paper is white
B. the light is white, the paper is green
C. the light is green, the paper is green
D. All of the above are possible
24. As shown, a beam of white light goes through a prism and is dispersed, forming a band of colored lights in Part B. Which
of the following is correct? (
)
A. a thermometer placed only in Part A will show temperature rising
B. Color 1 is violet
C. A heating lamp in a bathroom emits lots of Color 2
D. Lights in Parts A and C are not visible to the human eye
25. Different objects absorb sun’s radiation to different extents. Xiao Ming thinks it may relate to the color of the object.
He paints several identical objects different colors and places them under a bright sun for 30 minutes, and then
measures the temperature increases of the objects. The part that “Xiao Ming thinks it may relate to the color of the
object” is ______ in scientific enquiry. (
)
A. Raising a question
B. Making a hypothesis
C. Doing an experiment
D. Analyzing evidence
Part Two: filling blanks (2 marks each blank, total 50 marks)
26. An object’s ability to absorb radiant energy depends on its ___________. Black objects absorb ________ (more or less)
heat from the sun than white objects.
27. When students line up for assembly in the morning, if everyone can only see the person in front of him/her, the line is
straight. This is because _____________________________________________________________________.
28. In 1666 Isaac Newton performed a famous _______________ experiment, and revealed the mystery of color. He allowed
sunlight to pass through a narrow slit and hit a prism. He saw a band of colored lights on a white screen placed on the
other side of the prism. As shown, from A to B in order, he saw red, orange, yellow, ________, blue, indigo and violet.
We know that below B there is also _________ rays that will make fluorescent print visible on a bank note.
29. “A leaf before your eyes will make mountains disappear” shows that _______________________________________.
30. Allow a beam of sunlight to pass through a prism, sunlight will disperse into colored lights. If you allow these colored
lights to go through an inverted prism again, they will merge into white sunlight again. This shows that sunlight is
composed of different colored ____________________ lights.
31. To make a pinhole image viewer, you need to insert a rolled up
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poster paper into the aluminium can. To better view the image,
you should use a semi-transparent tracing paper to cover ______
(A or B) end of the paper roll. When you move the roll inside the
can away from the pinhole, the image on the screen will be ________
(brighter or dimmer).
32. Books and bedding may grow moldy after a long storage in the house. People often put them out in the sun to get rid
of the dampness and germs. A student science group intended to find out which particular radiation from the sun
actually kills germs, and carried out the following plan.
1). From research they learnt that sun’s radiation mainly composed of infrared, _________ and ultraviolet rays
2). They made a hypothesis: infrared rays kill germs
3). They made the following measurements:
Radiation type
Infrared
Red
Yellow
Green
Blue
Violet
Ultraviolet
Germ count before sunlight
20
20
20
20
20
20
20
Time of exposure to sunlight
4h
4h
4h
4h
4h
4h
4h
Germ count after sunlight
20
20
20
20
20
20
0
4). Conclusion: the hypothesis is _______________ (correct or incorrect). The type of radiation in the sun that kills
germs is __________________.
33. The dispersion of sunlight means that it is a __________ (monochromatic
or compound) light. In the diagram, a beam of white light strikes a face of
a prism. The screen on the other side of the prism, in the range from c to d,
shows colored lights. In Part (a), at c end, you will see ______ light. In Part (b),
at c end, you will see _______ light.
34. Among the sun, the moon and fireflies, __________ is NOT a light source. In vacuum light travels at _____________
m/s. In the medium of uniform density light travels in ___________ lines.
35. Xiao Hua does a pinhole imaging experiment.
1) fixing the distance between pinhole and screen, move candle away from the hole, the image on the screen will ---become __________ (bigger or smaller)
2) fixing the distance between candle and pinhole, he changes the distance between screen and pinhole (s) and ---measures the height of the flame (h) each time. The following results are produced. He draws the correct ----conclusion
that ________________________________________________________________________________.
Distance of screen from pinhole (s/cm)
1.0
2.0
3.0
4.0
5.0
Height of flame (h/cm)
2.0
4.0
6.0
8.0
10.0
36. Solar and lunar eclipses are interesting phenomena. Picture A shows Xiao Hong and Xiao Mei used a pan of black ink
water to view a solar eclipse. The reason they did this was to _____________________________________________.
The way in which solar eclipse is formed is shown in diagram B. It is caused by the fact that light travels in __________
lines. In Diagram C, when the Earth is in Area ______ (A, B or C), total solar eclipse will be seen.
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