CBSE Class 10 Answered

Swim goggles and diving masks work by providing a pocket of air in front of you that enables light rays to travel to and through your eyes in a more precisely focused way.

Without that chamber of air in swim goggles and diving masks, your eyes would contact the water directly. Because light rays cannot effectively travel through water for your eyes to achieve proper focus, your vision under these circumstances is actually worse than legal blindness.

If you wear prescription eyewear because you are near sighted or far sighted, you also will need corrective lenses to see clearly underwater.