3.2 LIGHT
Exam-style questions
1 Figure 3.2.49 shows a ray of light PQ striking a
mirror AB. The mirror AB and the mirror CD are
at right angles to each other. QN is a normal to
the mirror AB.
A Figure 3.2.49
a State the value of the angle of incidence
of the ray PQ on the mirror AB.
b Copy the diagram, and continue the ray
[2]
PQ to show the path it takes after
reflection at both mirrors.
[3]
c State the values of the angle of reflection
at AB, the angle of incidence at CD and
the angle of reflection at CD.
[3]
d Comment on the path of the ray PQ and
the final reflected ray.
[2]
[Total: 10]
Alternative to Practical
3 You are asked to test the law of reflection,
You are given a set of pins, a plane mirror, a
protractor, a ruler, some modelling clay and a
large sheet of paper attached to a cork board.
Describe a method you could use to test
the law. Include a sketch of your proposed
experimental arrangement.
b Draw up a table with headings showing
what measurements you would take.
c How would you decide if your results were
in agreement with the law of reflection?
d Mention two precautions you would take
to ensure accurate results.
(4)
[2]
[2]
(2)
[Total: 10)
4 In Figure 3.2.51 a ray of light 10 changes
direction as it enters glass from air.
2 a Which of the following statements is a true
description of the image in a plane mirror?
A Upright, real and larger
C Inverted, real and smaller
B Upright, virtual and the same size
D Inverted, virtual and the same size
[1]
b A person stands in front of a mirror
(Figure 3.2.50). How much of the ror is
used to see from eye to to
2
Figure 3.2.51
[1]
a State the name given to this effect.
b Identify the normal.
c State whether the ray is bent towards or
away from the normal in the glass.
d State the value of the angle of incidence
in air.
(1)
[1]
[1]
[1]
[Total: 51
State the value of the angle of refraction
in glass.
5 Figure 3.2.52 shows rays of light in a semicircular
glass block.
A Figure 3.2.50
c A girl stands 5m away from a large plane
mirror. How far must she walk to be 2 m
away from her image?
A Figure 3.2.52
[4]
[Total: 7]
a Explain why the ray entering the glass at
A is not bent as it enters.
[1]
Bexplain why the ray AB is reflected at B and not refracted.
[2]
CRay CB does not stop at B. Copy the diagram and draw its approximate path after it leaves B.
Exam-style questions
1 Figure 3.2.49 shows a ray of light PQ striking a
mirror AB. The mirror AB and the mirror CD are
at right angles to each other. QN is a normal to
the mirror AB.
A Figure 3.2.49
a State the value of the angle of incidence
of the ray PQ on the mirror AB.
b Copy the diagram, and continue the ray
[2]
PQ to show the path it takes after
reflection at both mirrors.
[3]
c State the values of the angle of reflection
at AB, the angle of incidence at CD and
the angle of reflection at CD.
[3]
d Comment on the path of the ray PQ and
the final reflected ray.
[2]
[Total: 10]
Alternative to Practical
3 You are asked to test the law of reflection,
You are given a set of pins, a plane mirror, a
protractor, a ruler, some modelling clay and a
large sheet of paper attached to a cork board.
Describe a method you could use to test
the law. Include a sketch of your proposed
experimental arrangement.
b Draw up a table with headings showing
what measurements you would take.
c How would you decide if your results were
in agreement with the law of reflection?
d Mention two precautions you would take
to ensure accurate results.
(4)
[2]
[2]
(2)
[Total: 10)
4 In Figure 3.2.51 a ray of light 10 changes
direction as it enters glass from air.
2 a Which of the following statements is a true
description of the image in a plane mirror?
A Upright, real and larger
C Inverted, real and smaller
B Upright, virtual and the same size
D Inverted, virtual and the same size
[1]
b A person stands in front of a mirror
(Figure 3.2.50). How much of the ror is
used to see from eye to to
2
Figure 3.2.51
[1]
a State the name given to this effect.
b Identify the normal.
c State whether the ray is bent towards or
away from the normal in the glass.
d State the value of the angle of incidence
in air.
(1)
[1]
[1]
[1]
[Total: 51
State the value of the angle of refraction
in glass.
5 Figure 3.2.52 shows rays of light in a semicircular
glass block.
A Figure 3.2.50
c A girl stands 5m away from a large plane
mirror. How far must she walk to be 2 m
away from her image?
A Figure 3.2.52
[4]
[Total: 7]
a Explain why the ray entering the glass at
A is not bent as it enters.
[1]