How are electromagnetic waves different than all the other waves

What are the applications of electromagnetic waves

In a simplified model of the human eye, the aqueous and vitreous humors and the lens all have a refractive index of 1.40, and all the refraction occurs at the cornea, whose vertex is 2.60 cm from the retina. what should be the radius of curvature of the cornea such that the image of an object 40.0 cm from the cornea’s vertex is focused on the retina?

4. if you were an astronaut on the moon, what would you experience? what would you see from your perspective?