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Determining Focal Length

  • Thread starter hardwork
  • Start date
  • #1
20
0

Homework Statement


Without her contact lenses, Kat cannot clearly see an object more than 70.0cm away. What should be the focal length of her corrective contact lenses?


Homework Equations


1/f = 1/p + 1/q


The Attempt at a Solution


1/f = 1/infinity + 1/-70.0cm = -0.0143cm
f = -70.0 cm

Would anyone be able to please check this answer? Thank you!
 
Last edited:

Answers and Replies

  • #2
rl.bhat
Homework Helper
4,433
5
Your answer is correct.
 

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