Summary

• Thin film interference
• Polarization
• Cameras

• The human eye
  • optical arrangement
  • nearsighted
    Example #1
    
    Example #2
    
    
  • farsighted
  • astigmatic
  
  
  
  
• The magnifying glass applet
  • image at infinity
  • image at near point
    
    Example #3
    
  
  
  
  
• The telescope
  • objective & eyepiece applet
  • magnification applet
    
    Example #4
    
  
  
  
  

sj6 36.q19
Is this person nearsighted or farsighted?
A. nearsighted
B. farsighted
C. neither
D. impossible to say
Answer







gc6 25.13
A person has a far point of 14 cm. What power contact lenses would the person need?
A. +7.14 D             B. +4.00 D
C. -7.14 D              D. -14.3 D
Answer







gc6 25.22
What is the focal length of a 3.5× magnifier for a relaxed (focused at infinity) normal eye?
A. 14.0 cm            B. 7.14 cm
C. 4.00 cm            D. 28.6 cm
Answer







gc6 25.31
An 8.0× binocular has 2.8 cm focal length eyepieces. What is the focal length of the objective lenses?
A. 80.0 cm            B. 44.6 cm
C. 35.0 cm            D. 22.4 cm
Answer







 



A. nearsighted
The upright, reduced, virtual image of the man's face behind the lens indicates the lens is diverging. Diverging lenses are used to correct nearsightedness. The converging lens for a farsighted person would produce an upright, magnified, virtual image of the face. Here is a comparison, nearsighted on the left and farsighted on the right:













 



C. -7.14 D













 



B. 7.14 cm













 



D. 22.4 cm