Looking directly at the sun (or a powerful laser) is dangerous because:
ASunlight ages the eye instantly
BConcentrated, high-intensity light can permanently damage the retina's light-sensitive cells; the lens of the eye focuses it onto a tiny spot like a magnifying glass, making the damage worse
CIt changes the colour of the iris
DThe pupil becomes too small
Answer & Solution
Correct answer: B. Concentrated, high-intensity light can permanently damage the retina's light-sensitive cells; the lens of the eye focuses it onto a tiny spot like a magnifying glass, making the damage worse
The eye's lens concentrates incoming light onto the retina — exactly the way a magnifying glass can burn paper. With the sun or a laser, the concentrated intensity exceeds what the retina can survive, killing photoreceptor cells. Damage to the retina is generally permanent because retinal cells do not regenerate.
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