Concept explainers
(a)
The focal length of lenses she required.
(a)
Answer to Problem 64E
The focal length lenses she required is
Explanation of Solution
Write the expression for the focal length of the lenses.
Here,
Conclusion:
Substitute
Simplify for the focal length.
Thus, the focal length lenses she required is
(b)
The near point without the glasses.
(b)
Answer to Problem 64E
The near point without the glasses is
Explanation of Solution
Write the expression for the power of eye at far point.
Here,
Write the expression for the power of the eye at near point.
Here,
Write the expression for the near point of the eye.
Here,
Conclusion:
Substitute
Substitute
Substitute
The near point without the glasses is
(c)
The near point with the glasses.
(c)
Answer to Problem 64E
The near point with the glasses is
Explanation of Solution
Write the expression for the power of eye at infinity.
Here,
Write the expression for the power of accommodation of the eye at near point with glasses.
Here,
Write the expression for the near point of the eye with the glasses.
Here,
Conclusion:
Substitute
Substitute
Substitute
The near point with the glasses is
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Chapter 24 Solutions
General Physics, 2nd Edition
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