New Near Point with Corrective Lens?

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In summary, the person needs a corrective lens with a power of -2.00D to see distant objects. Using the formula 1/f = 1/v + 1/u, where v is the image distance and u is the object distance, the new near point with the corrective lens is calculated to be 49.7m. This is due to the person being nearsighted and needing glasses to help see distant objects, which moves the near point farther out.
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Homework Statement


So I've calculated the person's corrective lens to need the power of -2.00D now I must find the new near point with the corrective lens on.

The initial near point is 15cm and I converted the -2.00D into cm, which is -50cm (I hope).

Homework Equations


I've used this formula -
1/f = 1/v + 1/u

v = image distance

u = object distance

The Attempt at a Solution


My attempt so far looks like this... I have an answer but need someone more experienced to tell me if it seems right:

1/f = 1/0.019m + 1/-0.35m = 49.7m

So would the new near point be 49.7m?

Any help would be really appreciated, thanks!
 
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The nearpoint without glasses is 15 cm. With the glasses on (assuming they near the eye), you need to find the object distance that gives a virtual image (right side up) from this corrective lens at m=-15 cm. You are correct in using ## 1/f=1/b+1/m ## with ## f=-50 ## cm. Your "b" will be positive. (editing this=originally, I thought the focal length of the corrective lens was positive.) It appears the person is nearsighted and needs glasses to help him see distant objects. In the process, it will move his nearpoint farther out. (Note: I don't know where your .019 and -.35 came from.)
 
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FAQ: New Near Point with Corrective Lens?

What is a new near point with corrective lens?

A new near point with corrective lens refers to the closest point at which a person can see clearly with the help of corrective lenses, such as glasses or contact lenses. This point is measured by an optometrist or ophthalmologist during an eye exam.

How is a new near point with corrective lens determined?

A new near point with corrective lens is typically determined by conducting a near point accommodation test. This involves having the person look at a small object or text and moving it closer until it becomes blurry. The distance at which the object becomes blurry is recorded as the near point with corrective lens.

Why is a new near point with corrective lens important?

A new near point with corrective lens is important because it helps determine the level of nearsightedness or farsightedness a person has. It also helps determine the strength of corrective lenses needed to improve their vision.

Can a new near point with corrective lens change?

Yes, a new near point with corrective lens can change over time. This is especially true for children and young adults, as their eyes are still developing and may require different levels of correction as they grow. It is important to have regular eye exams to monitor any changes in near point with corrective lens.

What should I do if my new near point with corrective lens is changing?

If you notice changes in your new near point with corrective lens, it is important to schedule an eye exam with your optometrist or ophthalmologist. They will be able to assess any changes and determine if a different prescription is needed. It is also important to follow any recommendations for wearing glasses or contact lenses as prescribed by your eye doctor.

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