Year 9 General Science – Light Trial Test 2014
Name: _______________________
Class: __________
Instructions: Write answers in the right-hand column.
Date: _______
Score: ____________ / 100 marks
Section A—Multiple choice (20 marks) 1 mark Each
1
Which ray below is the one that is reflected from a plane mirror?
B
1
2
3
4
5
6
7
Perspex has a higher refractive index (density) than air. Light entering air from
perspex will:
A slow down slightly and be bent towards the normal
B slow down slightly and be bent away from the normal
C speed up slightly and be bent towards the normal
D speed up slightly and be bent away from the normal
Light travels with a speed at about
A. 300,000 meters per second
B. 3,000,000 meters per second
C. 30,000 kilometres per second
D. 300,000 kilometres per second
Which of the Electromagnetic radiation (EMR) has the highest frequency?
A infrared light
B radio waves
C X-rays
D microwaves
Which of the following waves does not belong to electromagnetic radiation?
A infrared light
B white light
C X-rays
D sound waves
When a pencil is viewed through water, it appears bent
because light:
A slows down as it passes from water to air
B is reflected at the surface of the water
C is refracted away from the normal as it passes from water
to air
D is refracted towards the normal as it passes from water to
air
What is the meaning of the formation of a REAL image?
A You can see the image of an object
B The image has the same size as the object
C The image can be focused on a screen
D The image that is formed by a plain mirror
D
1
D
1
C
1
D
1
C
1
C
1
Year 9 General Science – Light Trial Test 2014
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9
10
11
12
13
14
15
16
The image produced by a convex lens when the object is inside the focal length:
A enlarged and upright
B diminished and inverted
C diminished and upright
D enlarged and inverted
Which of the following(s) can form an image on a screen?
A plane mirror
B concave mirror
C a transparent glass
D convex mirror
Which of the radiation is involved in scanning luggage at the airport?
A X-rays
B microwaves
C gamma rays
D blue light
What colour will a green leaf placed in green light appear to be?
A black
B green
C red
D blue
A
1
B
1
A 1
B
The image produced on the back of our eyes (retina) is:
A virtual, upright and enlarged
B virtual, inverted and diminished
C real, upright and enlarged
D real, inverted and diminished
D
What colour is transmitted when cyan light is shone on a green filter?
A cyan
B
blue
C
green
D
red
C
Which colours are absorbed by blue paint?
A blue only
B red, orange and yellow
C green, blue, indigo and violet
D red only
B
In the eye disorder known as long-sightedness, the image of an object forms
behind the retina. Long-sightedness is corrected by bringing the image
forward using:
A convex lenses that bend the light less
B convex lenses that bend the light more
C concave lenses that bend the light less
D concave lenses that bend the light more
Which is the correct image formed by the plain mirror?
1
1
1
1
B
1
C
1
17
In a primary rainbow, what colour is at the top of the rainbow?
A blue
B green
C orange
D red
D
1
Year 9 General Science – Light Trial Test 2014
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19
20
Comparing microwaves and ultraviolet rays,
A microwaves have lower frequencies
B ultraviolet rays have longer wavelengths
C microwaves have more energy than ultraviolet rays
D ultraviolet rays are more visible than microwaves
Which of the following colours of light is most strongly refracted?
A red
B yellow
C green
D violet
A
1
D
Three primary colours of light which mix to make white light, they are:
A yellow, green, red
B cyan, yellow, magenta
C green, blue, red
D red, green, orange
1
C
1
Section B—Written answers (60 marks)
1
2
3
60o
60o
If a light ray strikes a mirror at an angle
of 30o to the mirror, what is:
a
the angle of incidence?
b
the angle of reflection?
a
b
What is meant by the refraction of light?
The bending of a light ray as it passes
from one substance into another
substance (different media)
2
The diagram on the right shows a light
ray travelling through air to the interface
between the air and a glass block.
2
Incident
ray
i
On the diagram, draw the normal, and a
possible path for the ray in the glass.
r
Label on the diagram: normal, angle of
incidence, angle of refraction, refracted
ray, incident ray
4
Which type of lens (convex or concave):
a is fatter in the middle than at the
ends?
b can produce a real image?
Refracted
ray
4
a convex
b convex
3
Year 9 General Science – Light Trial Test 2014
5
Curved mirrors are usually shown in
cross-sectional views to indicate their
shapes. Three such shapes are shown
below.
a Diagram I = convex mirror
Diagram II= parabolic mirror
Diagram III = concave mirror
b convex mirror – light diverges out
parabolic mirror – light reflects in a
parallel manner
concave mirror – light converges
a Which mirror is which?
(parabolic, convex, concave )
b What happen when a spot light is
placed in front of each of these
mirrors?
c Give one use of each of these
mirrors.
6
You have two lenses. Lens A is fat and
highly curved. Lens B is flatter, being
only slightly curved. Which lens (A or
B) can be expected to:
a
bend light the most?
b
have the longest focal length?
c convex mirror – security mirror in
shops
parabolic mirror – torch, headlight in
cars
concave mirror – shaving mirror, dental
mirror
9
a
b
Lens A
Lens B
2
7
What is the name given to the:
a splitting of light into component
colours by a prism?
b Why do light split up into rainbow
colours?
c List all the rainbow colours in the
correct order.
a
Dispersion
b
White light consists of different
colours and they travels at different
speed and bend differently
c
Red, Orange, Yellow, Green,
Blue, Indigo, Violet
4
Year 9 General Science – Light Trial Test 2014
8
Complete the following table on EMR.
Radiation
Special Feature
Uses
microwave
wavelengths ranging
from 1 mm to 1 m
cooking
ultraviolet
just beyond the visible
spectrum
sun tanning
radiowaves
longest wavelength and
lowest frequency
telecommunication
gamma ray
shortest wavelength and
the most powerful energy
cancer treatment
visible
only spectrum visible to
human eye
photosynthesis
10
9
This question concerns colours of light.
a Name the primary colours of light.
b Why are they called primary colours?
c Name the secondary colours of light.
d Why are they called secondary
colours?
e Is White a colour?
a
Red, green and blue.
b They can be combined in various
proportions to form all the other
colours.
c Cyan, magenta and yellow.
d They are produced when just two
primary colours overlap.
e Yes, white is a combination of
rainbow colours..
5
10
The diagram below shows combinations
of light colours.
State the name of the colours seen
in a to d.
a
b
c
d
cyan
magenta
white
yellow
4
Year 9 General Science – Light Trial Test 2014
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12
What colour (if any) is transmitted
when:
a white light is shone on a
blue filter?
b red light is shone on a
green filter?
c magenta light is shone on a
red filter?
a
b
c
What colour or colours of light are:
a absorbed by a blue shirt?
b reflected by a red shirt?
c combined to produce yellow light?
a
b
c
blue
no light
red
3
all colours other than blue
red
red and green
3
13
a What are the three ‘primary colours
of pigments’?
b Give an example of secondary colour
created by 2 primary colours.
a
b
cyan, magenta and yellow
e.g blue+yellow = green
blue+red = purple
red+yellow = orange
2
14
a
b
c
People having short-sightedness is due to the fact that the eyeball is
longer than the normal.
The image of the far object is formed in front of the retina.
Complete the diagrams to illustrate the problem.
d
What lens can be used to correct this problem? Convex lens – it diverges the
light further and reaches the retina – giving sharp focus of image.
8
Year 9 General Science – Light Trial Test 2014