The diagram shows the basic structure of an eye.
(a) Light entering the eye is refracted by the eye lens
(i) What happens to light rays that are refracted? (1 mark)
(ii) For a person with perfect vision, where in the eye is the light refracted by the eye brought to focus? (1 mark)
(iii) The eye is able to focus on both near and distant objects. Explain how it is able to do this. (4 marks)
(iv) Name the other part of the eye that also refracts light? (1 mark)(b) A student has poor eyesight and needs to wear a pair of glasses. Each of the lenses used in the glasses has a power of –2.5 D.
(i) Does the student have long sight or short sight?
Give a reason for your answer. (1 mark)
(ii) What eye defect may be causing the student’s poor eyesight? (1 mark)
(iii) Calculate the focal length, in metres, of the lenses used in the glasses.
Write down the equation you need to use and show how you work out your answer. (2 marks)
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