Slide version
Light refracts when it goes from the air into water or glass. The reason is like this: Light travels more slowly in water or glass than in the air and the lower side of light reaches the water earlier than the upper side of light. When the upper side reaches the water, the lower side is going more slowly already.
In other words, as is shown in the left photo, the difference in speed within the light going through the medium causes the refraction of the light when it travels from the air into the water.
I made a refraction experiment.
As in the photo above, if you put a coin in the container without water in it, only a small portion of the coin can be seen. However, when there is enough water in the container, most of the coin can be seen!
The figure above: without water, the coin cannot be seen.
With water, the refraction of light happens, as is shown in the figure above, and the coin can be seen in a different place than where it is actually.
Total reflection
2015 身の回りの光と色の現象
Refraction of light
Light refracts when it goes from the air into water or glass. The reason is like this: Light travels more slowly in water or glass than in the air and the lower side of light reaches the water earlier than the upper side of light. When the upper side reaches the water, the lower side is going more slowly already.
In other words, as is shown in the left photo, the difference in speed within the light going through the medium causes the refraction of the light when it travels from the air into the water.
I made a refraction experiment.
video
As in the photo above, if you put a coin in the container without water in it, only a small portion of the coin can be seen. However, when there is enough water in the container, most of the coin can be seen!
The figure above: without water, the coin cannot be seen.
With water, the refraction of light happens, as is shown in the figure above, and the coin can be seen in a different place than where it is actually.
Total reflection
2015 身の回りの光と色の現象