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Spectacles, Focal length and Lens Formula

  • Thread starter ZedCar
  • Start date
  • #1
354
1

Homework Statement



When using the lens formula: 1/f = 1/u + 1/v

for someone who has short sightedness and cannot focus on objects on objects more than 2.5m away, I get:

1/f = 1/infinity + 1/-2.5
f = -2.5 m


If using the formula for someone who had long sightedness and could not focus on objects closer than 2.5m does this mean the equation would be:

1/f = 1/infinity + 1/2.5
f = 2.5 m

Thanks! :smile:


Homework Equations



1/f = 1/u + 1/v


The Attempt at a Solution

 

Answers and Replies

  • #2
354
1
bumpity
 
  • #3
354
1
Anyone?
 

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