Page 204 - Physics_Form_2

Physics for Secondary Schools

7. From the same point, draw another 9. Measure the object distance, the
ray that passes un-deflected through image distance, the object size
the optical centre. You may also and the image size. Calculate
choose to draw a ray through the magnification.
focal point and refract it according 10. Repeat steps 5 to 9 for different
FOR ONLINE READING ONLY
to the refraction rules. positions of the object. That is,
8. Locate the point at which the the object at the point 2F , object
1
refracted rays intersect and draw between 2F and F object at F and
1
1
1
an arrow from the principal axis object between F and O.
1
to the point of intersection. Figure 11. Use simulation software to verify
5.38 shows the image formation by your findings by adjusting the object
a convex lens for an object beyond position digitally. Record the image
the point 2F . distances and characteristics.
1

12. Summarise your results using a table and also in spreadsheet software as shown
in Table 5.5.

M
A

C 1 B' C 2
B 2F F O F 2F
1 1 2 2

A'
u
N f
v

Figure 5.38

Questions
(a) What are the positions (image distance) of the images formed for different object
positions?

(b) Describe the nature of the images formed. That is, are the images for various
object positions real or virtual?
(c) Are the images for objects at different positions enlarged, the same or diminished?

198
Student’s Book Form Two

Physics Form 2 Final.indd 198 25/10/2025 10:28