Our eyes function like a camera. In this video, Professor Pipette will demonstrate how a human eye works using a DIY Pinhole camera. When light falls on any object, a part of it reflects off and spreads out as waves. When these waves reach the eye, light receptors in the retina convert them to electrical signals, which are, subsequently, passed to the brain through the optic nerve. The brain forms images from these signals. Just like a camera, the lens of the eye focusses light signals on the retina. Remember, we need light to see, but too much light is not good for eyes.
The video satisfies the 4-PS4-2 requirement of fourth-grade science proficiency.
Students who demonstrate understanding can: 4-PS4-2. Develop a model to describe that light reflecting from objects and entering the eye allows objects to be seen.