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Solution - Defects of Vision and Their Correction

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Question

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.

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Solution for concept: Defects of Vision and Their Correction. For the course 9th - 10th SSC (English Medium)
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