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.
Related questions
Which property of a concave mirror makes it suitable for a dentist?A ray travelling parallel to the principal axis of a concave mirror is reflected:Where must an object sit for a concave mirror to form a virtual, magnified, erect image?What quantity is measured in lux and describes how many lumens fall on each square metre oFor yellow light with a wavelength of 6.00 x 10^-7 m, what frequency does c equals f timesOne light year is the distance light travels in one year. What is that distance in kilometA photographer measures 39.8 lux from a 2,000 lumen bulb held 2.00 m away, using illuminanPolarized sunglasses cut down glare from a lake. How do the lenses achieve this?