FOCUS QUESTION
How does light behave?
SPECIFIC OBJS
1. Value individual effort and team work
2. Investigate the properties of light
3. Investigate
some effects of reflection/refraction in everyday life
4. Carry out
fair tests in conducting investigations on the properties of light
CONTENT SUMMARY
Light is a form of energy. It is detected by the eyes and it enables vision. Light behaves differently when it comes in contact with different types of materials. All objects are either transparent, opaque or translucent.
Light can be reflected, refracted or absorbed.
PROPERTIES OF LIGHT include:
ü Light travels in a straight line from a source.
ü Light travels fast
ü Light has a dual nature
ü Light can vary in intensity
ü Light interacts with matter
ü Light is comprised of many colours
Light carries energy and information
ENGAGE
Let's review our last lesson on light.
What is reflection?
Which materials are considered good reflectors?
What are the properties of light we have looked at?
What are opaque materials?
What are transparent materials?
Why are shadows formed?
EXPLORE
Today we are going to look at another property of light.
Look at the chart below. We are going to perform the given activity.
Now can you tell what refraction is?
Why did the pencil appear bent?
What is the property of light discovered?
Now I want you to watch the video clip below. It will show you what happens to light as it passes through different lenses.
Here are two closer diagrams that show the behaviour of light as it passes through concave and convex lenses.
Let us take a look at what happens to light as it passes through different colours.
Have you ever wondered why things have different colours.?
Why some objects appear black/white?
Let us watch the video below to learn more?
EXPLAIN
Explain what refraction is.
How does light behave as it passes through water, lenses, mirrors?
Explain why the behaviour occurs for each.
EXTEND/ELABORATE
Watch this video clip to learn more about refraction. Please make your notes.
EVALUATE
1. Why does the straw below appear bent?
(a) Light is being reflected (b) It is showing an image
(c) Light is being refracted (d) The straw is opaque
2. What property of light is tested below?
(a) reflection (b) refraction (c) image (d) echo
3. Complete the worksheet below.
4. Complete the worksheet below.
5. The diagram below shows a student using a flashlight to shine a light on a mirror.
What is the most likely result of the light shining on the mirror? The light will ______ .
(A) pass through the mirror
(B) be absorbed by the mirror
(C) shine above the shelf
(D) make the mirror luminous
6. The table below shows what should happen to light when it comes in contact with different objects.
Which object has the tick mark at the incorrect location?
(A) coin (B) clear glass window (C) silver spoon (D) candle
7. What will happen when light passes through a concave lens?
(a) light rays will diverge (b) light rays will converge
8.Why does an object appear black?
(a) all light is reflected (b) all light is absorbed (c) all shadows are formed (d) all light pass through
9. Why does an object appear white?
(a) all light is reflected (b) all light is absorbed (c) shadows are formed (d) light is refracted
10. Name the lenses below.
11. Read each statement below. Indicate whether a statement is true.
STATEMENT
|
True
|
False
|
In a plane or flat mirror, right side of the object appears to be on the left side, and left appears to be on the right.
|
0
|
0
|
In a plane or flat mirror, the image formed is erect and the same size as the object.
|
0
|
0
|
The image formed in a plane mirror is at the same distance behind the mirrors as the object is in front of it.
|
0
|
0
|
When an object is placed before a mirror that curves inwards, the image formed is upside down and much smaller than the object.
|
0
|
0
|
An image formed by a mirror that bulges out is erect but smaller in size than the real object.
|
0
|
0
|