What Is the Focal Length of Veronique's Glasses for Clear Vision?

AI Thread Summary
Veronique is nearsighted and can only see clearly up to 6.50 m without contacts, while her old glasses allow her to see up to 8.00 m. The focal length of her glasses can be calculated using the lens formula 1/p - 1/q = 1/f, where p is the object distance and q is the image distance. A user attempted to solve for the focal length and arrived at -7.98 cm but is unsure how to determine the greatest distance for clear vision with the glasses. Further guidance is needed to complete part b of the problem. The discussion highlights the challenges faced in applying the lens formula to practical scenarios.
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Homework Statement


Veronique is nearsighted; she cannot see clearly anything more than 6.50 m away without her contacts. One day she doesn't wear her contacts; rather, she wears an old pair of glasses prescribed when she could see clearly up to 8.00 m away. Assume the glasses are 2.0 cm from her eyes.

a. What is the focal length of Veronique's glasses?
b. What is the greatest distance an object can be placed so that she can see it clearly with these glasses?

Homework Equations



1/p-1/q=1/f

The Attempt at a Solution



I literally have no idea where to start. any hints appreciated
 
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so i got -7.98 for the focal length. but i don't know how to do b
 

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