What Should Be the Focal Length of Kat's Corrective Contact Lenses?

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Kat requires corrective contact lenses with a focal length of -70.0 cm to see objects clearly beyond 70.0 cm. The calculation uses the lens formula 1/f = 1/p + 1/q, where p is the object distance and q is the image distance. The solution confirms that the focal length is negative, indicating a diverging lens is needed. The answer has been verified as correct by other participants in the discussion. This ensures Kat will achieve clear vision with the appropriate lenses.
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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!
 
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