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P. 140
Physics for Secondary Schools
along your line of sight, as shown in representing the location of the
Figure 4.14. image. This line will be perpendicular
to the mirror line and therefore the
Mirror normal.
11. Using a protractor, measure the
Line of sight
FOR ONLINE READING ONLY
angle of incidence and the angle of
2 4 reflection.
1 3
Questions
Figure 4.14 (a) Compare the object’s size with the
size of the image formed in Step 3.
6. Remove the mirror and use a ruler (b) Discuss your results in step 9.
to draw a line through the positions (c) Compare the two angles formed by
of pins 1 and 2. This represents the the rays and discuss your results.
incident ray. (d) Comment on the position of the
7. Draw a line through the positions incident ray, the reflected ray and
of pins 3 and 4. This represents the the normal.
reflected ray.
8. Extend the lines until they intersect. The image of the pin in the mirror is
The point of intersection is where identical in size and shape to the actual
the image appears, as shown in pin. This shows that both the object and
Figure 15.
its image have the same size. Also, the
Location of image distances of the object and its image from
the mirror are equal. The activity also
demonstrates that the angle at which light
hits the mirror (angle of incidence) equals
the angle at which it reflects (angle of
reflection). Furthermore, the incident ray,
reflected ray, and the normal line all lie
within the same plane.
Figure 4. 15
Image formed by plane mirrors
9. Measure the shortest distance When we look in a mirror, we do not
from pin 1 to the mirror line. Also, see the actual object but rather an image
measure the shortest distance from created by light rays reflecting off the
the location of the image to the mirror’s surface. These reflected rays
mirror line. adhere to the laws of reflection. Although
10. Draw a line through the midpoint the image forms in our eyes, it appears
of the mirror line and the point to be located behind the mirror, despite
134
Student’s Book Form Two
Physics Form 2 Final.indd 134 25/10/2025 10:27
