Question

In H.G. Wells's classic story The Invisible Man, a man manages to change the index of refraction of his body to 1.0 ; thus, light would not bend as it enters his body (assuming he is in air and not swimming). If the index of refraction of his eyes were equal to one, would he be able to see? If so, how would things appear?

Short answer

Explain your answer. Answer: No, the Invisible Man would not be able to see clearly if the index of refraction for his body and eyes is equal to 1. The light entering his eyes would not bend or focus due to the lack of change in the refractive index, resulting in a blurry and out-of-focus image on his retina. This would make it difficult for him to recognize objects or details.

Step-by-step solution

Understand the index of refraction

When light travels from one medium to another (for example, from air to water), it changes speed and direction, leading to a change in the path of the light. The index of refraction (n) is a measure of how much a material slows down light compared to a vacuum. The higher the index of refraction, the more a light ray bends when entering a medium. The refractive index of air is approximately 1, and the refractive index of the cornea and lens of the human eye is around 1.38.

Understand how light enters the eye and is focused on the retina

In the human eye, light enters through the cornea and the lens. These two transparent structures work together to bend and focus light on the retina, where the light-sensitive cells detect the light and send signals to the brain, resulting in vision. The bending and focusing of light is crucial for clear vision because it helps in creating a sharp image on the retina.

Analyze the situation with the Invisible Man's index of refraction

In this scenario, the index of refraction for the Invisible Man's body and eyes is 1, meaning that light would pass through his body and eyes without bending. If this were the case, the cornea and lens would not bend or focus light onto his retina.

Determine the Invisible Man's vision

Since the light entering the Invisible Man's eyes would not bend or focus, the light would not be focused on his retina, causing him to see a very blurry and out-of-focus image. In conclusion, if the Invisible Man's body and eyes have an index of refraction equal to 1, he would still be able to see, but the image would be extremely blurry and out-of-focus, making it difficult to recognize any objects or details.