Do people underwater looking at something out of the water have a wider visual field than if they were out of the water or if they were looking at something else underwater? This question can be answered using the optical path shown in Fig. 1; the eye can see a wider range when in a pool of water due to the refraction of light at the air–water interface (L2 > L1). However, during an experiment using a waterproof camera, an unexpected phenomenon was observed that contradicts previous analysis. Displaying and analyzing this unexpected experimental phenomenon is very interesting, and can also serve as a teaching case for physics teachers for students to discuss. The description of the experiment and analysis of this unusual phenomenon is presented below.
The experimental setup is depicted in Fig. 2, where a waterproof camera (brand: XTU MAX, referred to...