(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

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!

2. Relevant equations

1/f = 1/u + 1/v

3. The attempt at a solution

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# Homework Help: Spectacles, Focal length and Lens Formula

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