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3 years ago

8

If a farsighted person has a near point that is 0.600 m from the eye, what is the focal length f2 of the contact lenses that the

person would need to be able to read a book held at 0.350 m from the person's eyes?

1 answer:

ra1l [238]3 years ago

7 0

Answer:

f = 0.84 m

Explanation:

given,

near point of the distance from eye(d_i) = 0.60 m

distance he can read (d_o)= 0.350 m

focal length of the contact lens = ?

now,

Using lens formula

$\dfrac{1}{f} = \dfrac{1}{d_0} + \dfrac{1}{d_i}$

$\dfrac{1}{f} = \dfrac{1}{0.35} + \dfrac{1}{-0.6}$

$\dfrac{1}{f} = 1.19$

$f = \dfrac{1}{1.19}$

f = 0.84 m

Hence, The focal length of the contact lens that person needed is equal to

f = 0.84 m

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We can solve this part by applying the impulse theorem, which states that the change in momentum of an object is equal to the product between the force applied on it and the duration of the collision:

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$\Delta p$ is the change in momentum

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