Science year 4 KSSR and science year 5 KBSM. Notes and exercise for light topic

1. Light
Chapter 5 year 4 (KSSR)
Chapter 6 year 5 (KBSR)

2. Light travels in a straight line until it strikes an object
or surface
Light from a torch
Light from lamp
Sunlight rays shine between
the tree trunk in the forest

3. Shadows are formed when light
is blocked by opaque object or
translucent objects.
Type of
object
Opaque
Object that does not
allow any light to pass
through it
Translucent
Object that allows
some light to pass
through it
Transparent
Object that allows
all light to pass
through it.

4. Factors affecting the size of shadows
Light source
Object
Core
shadow
Shadow
cone
Cast
shadow
Screen
When the distance between
the object and the light
source increases, the size of
the shadow decreases.
When the distance between
the object and the light
source decreases, the size of
the shadow increases.

5. Factors affecting the shape
of shadows
The position of the
light source
The orientation of the object

6. Reflection of light
When light falls on an object, it bounces
off the surface of the object
Angle of
incident
Angle of
reflection
Ray diagram
Reflection of an image
in a mirror
We can see an
object because
the object
reflects light
into our eyes
An object with hard, smooth and shiny surface can reflect
light better than an object with uneven, soft and rough
surface.

7. Refraction of light
When light travels from a
medium to another medium.
The straw looks
bent in the water. The alphabets appear
larger in size when
using magnifying glass.
When the sun shines on
the rain droplets, the
light will be refracted.

8. Question
1. Which statements
explain the properties of
light?
A. P and Q
B. R and S
C. Q and S
D. Q and R
P Light travels in a straight
line
Q Light can be reflected
R Light can be destroyed
S Light cannot be refracted
2. Diagram above shows
the side mirror of a car.
What is the function of
the mirror?
A. Gives light
B. Absorbs light
C. Refracts light
D. Reflects light
3. What are the
characteristics of a
surface that reflects
light well?
A. Dark and soft
B. Rough and uneven
C. Dull and smooth
D. Shiny and smooth

9. Question
Light source
Object
Core
shadow
Shadow
cone
Cast
shadow
Screen
P
Q
R
4. If the object is placed at position P,
Q, R respectively, predict the size of
the shadow.
A.
B.
C.
D
P Q R

10. Teacher Halim asks his pupils to carried out an investigation to investigate how the distance between object and source of light affect the
shadow’s size. Diagram 1 below shows the arrangement of apparatus for this investigation. The result of the investigation are as in the
Diagram 2 below.
Bayang-
bayang
Bol
aSumbercah
aya
Skri
n
Shadow
Shadow’s
size
Screen
BallSource of
light
0
5
10
15
20
25
30
35
40
45
10 20 30 40
The size of
shadow (cm)
Distance of ball
from light
source (cm)
a) What is the aim of this investigation?
____________________________________________
b) State the pattern of changes of shadow’s size if the distance
of the ball from the light source increases.
____________________________________________
c) Based on this investigation, state the:
Diagram 1 Diagram 2
i) Manipulated variable:_________________________
ii) Responding variable:_________________________
d) Write one hypothesis based on this investigation.
____________________________________________
e) Predict what would happen if the ball is replaced with a
transparent glass
____________________________________________

11. Diagram 3 below shows an investigation to study the properties of light. The apparatus use are candle cardboard with
hole and cardboard holder.
Diagram 1
a) What is the properties of light studied in the above
investigation?
____________________________________________
b) What can be observe when the student look through the
hole A when the card board is arranged at the same height?
____________________________________________
c) What would happen if cardboard B is moved a bit to the
left?
____________________________________________
c) Give one tool that can replace candle in this
investigation?
____________________________________________
e) Write a conclusion based on the investigation?
____________________________________________