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Question
Give Reason:
When you enter into a dark room from bright because of sunlight, you can not see things for a few seconds.
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Solution
In bright light the visual purple or rhodopsin pigment is destroyed and the diameter of the pupil is reduced to allow the entry of less light.
RELATED QUESTIONS
In a Std. X class out of 40 students 10 students use spectacles, 2 students have positive power and 8 students have negative power of lenses in their spectacles.
Answer the following questions:
(1) What does the negative power indicate?
(2) What does the positive power indicate?
(3) Generally which type of spectacles do most of the students use?
(4) What defect of eyesight do most of the students suffer from?
(5) Give two possible reasons for the above defect.
Name one defect of vision (or eye) which cannot be corrected by any type of spectacle lenses.
Name an old age eye defect. What happens in it?
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Name the problem she is facing.
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Draw a labeled diagram to show how the above mentioned defect is rectified using the lens named above.
Observe the figure whether it is correct or not and explain the phenomenon.
Observe the figure and answer the following questions:
- Name the defect of vision represented in the above figure.
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