2. Table of Contents...
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Introduction: Optics and Magnification
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Applications and Examples: Optics
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Applications and Examples: Magnification
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Question
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Hypothesis
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Materials
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Procedure: Steps to constructing the apparatus
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Experiment
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Data (of magnifying glass)
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Data (of nearsighted lens)
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Magnification Calculations
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Conclusion
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Sources
3. Introduction: Optics and
Magnification
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Optics is a branch of physics which studies
the properties of light and how it behaves
when travelled through
certain objects/ matter.
Optics are widely used to aid the human
eye to see various objects clearer than
if it were to view the object alone.
Magnification refers to the process of
enlarging an object in appearance,
not physically.
Magnification enables one to increase
the resolution of an objects appearance
to help get a better visualization.
4. Applications and Examples:
Optics
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Applied in science: Astronomy,
photography, medicine, etc.
Everyday objects: Mirrors, lenses
(glasses- to help us view near/ far),
and a magnifying glass.
Example: Looking through a glass
filled with water. Objects through glass
appear smaller due to light refraction.
5. Applications and Examples:
Magnification
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Application: Magnifying lens is used to compare the apparent size
(through the lens) over the actual size (real, physical size) of the object.
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Equation: Magnification = Apparent Size/ Actual Size
Magnification may vary depending
on its optical distance (how close the
lens is to the object).
Applications in everyday technology:
Microscopes (to enlarge tiny objects
in detail) and telescopes (to see far
objects closer).
6. Question
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If I increase the height of the magnifying
glass/ lens, will the object appear bigger or
smaller through the lens?
What happens if I change the magnifying
glass to a reading lens or a nearsighted
lens.
7. Hypothesis
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If I increase the height (greater optical
distance) of the magnifying glass, then the
object’s measurement would decrease.
8. ✦
A sturdy ruler
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Tape
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Little strip of paper
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Black marker
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Materials
Scissors
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4 small objects: penny, short string,
sim card, and a paperclip
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A magnifying glass
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Box (used as support to hold the ruler straight)
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Rubber band/ tie (used to hold the magnifying glass in place on the ruler
and to make it easier to adjust its position).
9. Procedure: Steps to
constructing the apparatus
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Start by taking the little strip of paper
and measure it according to the diameter
of the magnifying lens using the ruler
and tape it along the lens of the
magnifying glass.
Construct the support of the
magnifying glass by taping the ruler
to the box.
Attach the magnifying glass using
the rubber tie.
Perform same steps except replace the
magnifying glass with a nearsighted lens,
then compare results.
10. Experiment
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I started off by measuring the object’s actual size. Once I
noted the measurement, then positioned the magnifying
glass starting at a 6cm height.
I then looked at object through the magnifying glass,
measuring it’s apparent size, with each time changing the
magnifying glass’s position (ending at 24cm).
I repeated this step for all 4 objects and kept track of my
results using a data chart.
11. Data: Magnifying Glass
(observations)
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I noticed that as I first positioned the magnifying
glass of each object at 6cm, its apparent size
was about double the actual size.
Once I began increasing the optical distance
(positioning the magnifying glass higher and
higher, further from the object),
the object’s apparent size began to decrease.
At 24cm, the object’s apparent size
appeared to be less than its actual size.
12. Data: Magnifying glass
Obje ct
Paperclip
Actu al Size (cm)
2.8cm cm
He igh t of le ns
(cm)
6cm
12cm
18 cm
24cm
Short string
1.7 cm
6cm
12cm
18cm
24cm
Sim card
1.5 cm
6cm
12cm
18cm
24cm
Penny
2 cm
6cm
12cm
18cm
24cm
Op tical siz e (cm)
4 cm
3 cm
1.5 cm
1cm
3 cm
2cm
1.5cm
0.5cm
3cm
2cm
1cm
0cm
2.5cm
1.7cm
1cm
0.5cm
13. Data: Nearsighted Lens
(observations)
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I observed that as the lens was closer to the object, its image
through the lens was almost similar to its actual size.
As I placed the lens at a higher level, increasing the optical
distance, I noticed the measurements of the objects through
the lens were shorter.
14. Data: Nearsighted lens
Ob je ct
Paperclip
Actu al Size (cm )
2.8cm cm
He igh t of le ns
(cm)
6cm
12cm
18 cm
24cm
Short string
1.7 cm
6cm
12cm
18cm
24cm
Sim card
1.5 cm
6cm
12cm
18cm
24cm
Penny
2 cm
6cm
12cm
18cm
24cm
Op tical siz e (cm)
2cm
1.3cm
1cm
0.6cm
1 cm
0.7cm
0.5cm
0.2cm
1cm
0.5cm
0.4cm
0.1cm
1cm
0.7cm
0.5cm
0.2cm
16. Conclusion
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As the magnifying lens was placed closer, the object’s apparent size
increased/ doubled. This is mainly due to the fact that objects normally
appear larger when a magnifying glass is placed closer. Our eyes
follow the light rays to the virtual image. Therefore, when observing an
object through a magnifying glass, we are viewing the image of the
object. However, this changes when we view objects through a
magnifying glass with a larger distance between because a magnifying
glass only enlarges the image when placed closer to the object, it no
longer works when placed further.
Nearsighted lens are made to assist in viewing far away objects
clearly. Unlike the magnifying lens, when the nearsighted lens was
placed at a distance closer to the object, its measurement (through the
lens) decreased. Even though we place the lens closer and closer to
the object, it will not enlarge, but will maintain its actual size.
Farsighted lens such as reading glasses would have similar results to
a magnifying glass compared to a nearsighted lens.
17. Conclusion (cont.)
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In conclusion, my hypothesis was correct. When the distance
between the object and the magnifying lens was increased
(further apart from each other), the object’s measurement
decreased.
