- Sections
- A. General Materials & Mathematics
- B. Statics
- C. Kinematics & Dynamics
- D. Rotational Mechanics
- E. Gravitation & Astronomy
- F. Fluid Mechanics
- G. Vibrations & Mechanical Waves
- H. Sound
- I. Thermodynamics
- J. Electrostatics & Magnetostatics
- K. Electromagnetic Principles
- L. Geometrical Optics
- M. Wave Optics
- N. Spectra & Color
- O. Vision
- P. Modern Physics
L7-21. Magnifying Glass - TV
Purpose
To illustratre how a magnifying glass works.◙
Equipment
TV camera, 20cm, 10cm and 5cm focusing lenses, and mounted rule on optical rail, TV monitor not shown
Setup Time
5 minutes.
Images
Description
The TV camera functions as the eye, so what the eye sees can be viewed on a monitor or the rear projection screen. First the focus is set at the near point of the TV lens (the near point of the eye), approximately 20 cm, and the ru le brought into focus as viewed on the monitor. The 20 cm focal length convex lens magnifying glass is then inserted as shown in the photo, the focus adjusted to infinity, and the object position adjusted slightly to obtain the best focus. The image size is the same! This demonstration illustrates that the function of a magnifying glass is not to "magnify" but to al
References
Lecture Demonstration Record Form. ◙Jay S. Huebner and Terry L. Smith, Why Magnification Works, TPT 32, 102-103 (1994).
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See pagesl1. light sources & light rays
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See pagesl2. plane mirrors
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See pagesl3. curved mirrors
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See pagesl4. refraction
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See pagesl5. total internal reflection
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See pagesl6. lenses
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See pagesl7. optical instruments
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See pagesl1. light sources & light rays
-
See pagesl2. plane mirrors
-
See pagesl3. curved mirrors
-
See pagesl4. refraction
-
See pagesl5. total internal reflection
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See pagesl6. lenses
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See pagesl7. optical instruments