Cambridge Science Checkpoint – IGCSE – IB/AS/A Level Mr.
Hoang - 0868614217
CAMRBRIDGE SCIENCE CHECKPOINT STAGE 8 WORKSHEET
UNIT 6 (PART 1). LIGHT REFLECTION AND REFRACTION
Hieu
Name: ………………………………………………………………………………………………………………........
1 Complete the sentences to describe the reflection of light.
Use the following words.
reflection equal to larger
incident smooth reflected
smooth
When a ray of light approaches a …………….. polished surface and the light ray bounces back, it is called
reflection
the …………………… of light.
incident
The ……………….. light ray that land on the surface is reflected off the surface.
reflected
The ray that bounces back is called the ………………… ray.
equal to
The angle of incidence is ……………………… the angle of the reflection.
Total: … / 5
2 The following diagram shows the light reflection.
the normal
the incident ray the reflected ray
(a) On the diagram, label the following factors:
- the incident ray.
- the reflected ray.
- the normal. [3]
(b) Describe how light reflection happens.
When they come across a flat and smooth surface they bounce back with a 90 degree angle. the angles that
……………………………………………………………………………………………………………………
are seperated by the normal is equal to eachother.
……………………………………………………………………………………………………………………
……………………………………………………………………………………………………………….. [2]
(c) State the value of the angle between the normal and the mirror.
90 degree
……………………………………………………………………………………………………………….. [1]
Total: … / 6
1
Cambridge Science Checkpoint – IGCSE – IB/AS/A Level Mr. Hoang - 0868614217
3 This question is about light reflection.
(a) Name the type of diagram that is used to demonstrate light reflection.
Ray diagram
……………………………………………………………………………………………………………….. [1]
(b) When you are standing in front of mirror, you could not see anything if the light is off.
Explain why.
because there is no light reflecting on the mirror and into your eyes therefore you can't see yourself and
……………………………………………………………………………………………………………………
everything.
……………………………………………………………………………………………………………………
……………………………………………………………………………………………………………….. [2]
Total: … / 3
4 Look at the diagram.
Name the factor that each of the following letters represents for.
Normal
A. ……………………………
Incident Ray
B. ……………………………
Reflected Ray
C. ……………………………
Angle between incident ray and mirror
D. ……………………………
Angle between incident ray and normal
E. ……………………………
angle between reflected ray and normal
F. ……………………………
Angle between reflected ray and mirror
G. ……………………………
Total: … / 7
5 Complete the following table, using the given numbers.
300 000 200 000 20 225 000
medium speed of light in that medium (km/s)
air 300 000
………………….
water 225 000
………………….
glass 200 000
………………….
Total: … / 3
2
Cambridge Science Checkpoint – IGCSE – IB/AS/A Level Mr. Hoang - 0868614217
6 Look at this diagram. It describes the observation when a pencil is put into a cup of water.
(a) What phenomenon is shown in the diagram?
Refraction
……………………………………………………………………………………………………………….. [1]
(b) Describe what causes the phenomenon you mention in (a).
light moves slower when they go through water so this causes light to change its trajectory
……………………………………………………………………………………………………………………
……………………………………………………………………………………………………………………
……………………………………………………………………………………………………………………
……………………………………………………………………………………………………………………
……………………………………………………………………………………………………………….. [3]
Total: … / 4
7 This diagram shows the light refraction.
(a) State the value of the:
55 degree
angle of incidence = ……………..
angle of refraction = ……………..
33 degree [1]
(b) Describe the change in direction of the refracted ray.
it bends 33 degree to the left
………………………………………………………………………………………………………………... [1]
(c) Compare the density of glass and air.
glass is a solid so it would be harder for light to passes through it. Air is gas so there will be nothing stopping
………………………………………………………………………………………………………………... [1] it
from passing through.
Total: … / 3
3
Cambridge Science Checkpoint – IGCSE – IB/AS/A Level Mr. Hoang - 0868614217
8 Complete the following sentences, using the words slower or faster only.
faster
(a) Light travels …………..…. in air than in water.
slower
(b) Light travels …………..…. in water than in air.
faster
(c) Light travels …………..…. in air than in glass.
slower
(d) Light travels …………..…. in glass than in air.
faster
(e) Light travels …………..…. in glass than in water.
(f) Light travels …………..….
slower in water than in glass.
Total: … / 6
9 Complete the following diagram to show the light refraction by drawing the normal and the refractive ray.
Normal ray
I
I
I
I
I
\
\
\ refractive ray
\
\
B
Total: … / 3
10 A light ray passes through three different materials, including water, air and glass, as shown in the
diagram below.
Identify each material.
material 1 …………………………….
Water
Glass
material 2 …………………………….
air
material 3 …………………………….
Total: … / 3
4
Cambridge Science Checkpoint – IGCSE – IB/AS/A Level Mr. Hoang - 0868614217
11 Complete the sentences to describe the reflection of light.
Use the following words.
greater away from the normal further away
bright measured smaller
toward the normal speeds up direction
speeds up
The light ……………….. direction
when it passes from glass or water into air. This causes it to change ……………...
away from the normal
We say that the light passing from glass or water into air is bent ………………………...
further away
That means the refracted ray is ……………….. from the normal than it would be if the incident ray just carried
on in a straight line.
You will also notice from the ray diagram that when light passes from glass or water into air the angle of
greater
refraction is …………….. than the angle of incidence.
Both of these angles are ……………..
measure from the normal.
Total: … / 6
12 Complete the following diagram to show the light refraction by drawing the normal and the refractive ray.
|
| Refractive ray
|
|
|
|
|
|
|
|
|
|
| Normal
|
|
|
|
|
Total: … / 3
13 Complete the following sentences, using the words larger or smaller only.
smaller than the angle of refraction.
(a) When light travels from water into air, the angle of incidence is …………..
Larger than the angle of refraction.
(b) When light travels from water into glass, the angle of incidence is ………..
larger
(c) When light travels from air into glass, the angle of incidence is ………….. than the angle of refraction.
Smaller
(d) When light travels from glass into air, the angle of incidence is ………….. than the angle of refraction.
Total: … / 4
