Without his glasses, Isaac can see objects clearly only if they are less than 4.7 m from his eyes. Required: What focal l

Question

Without his glasses, Isaac can see objects clearly only if they are less than 4.7 m from his eyes.

Required:
What focal length glasses worn 2.1 cmcm from his eyes will allow Isaac to see distant objects clearly?

in progress 0
RobertKer 5 years 2021-08-06T12:10:46+00:00 1 Answers 24 views 0

Answers ( )

  1. Ladonna
    0
    2021-08-06T12:11:48+00:00
    Reply

    Answer:

    The focal length is  f = -4.721 \ m

    Explanation:

    From the question we are told that

      The  image distance  is  v = 4.7 + (2.1 *10^{-2}) = - 4.721 \ m the negative means  image is formed behind the lens

    Generally the object distance is  u = \infty this mean the light ray coming from the object are parallel to each other

    So from lens equation

           \frac{1}{\infty } - \frac{1}{4.721} = \frac{1}{f}

    =>   f = -4.721 \ m

Leave an answer

Browse

Giải phương trình 1 ẩn: x + 2 - 2(x + 1) = -x . Hỏi x = ? ( )