Mirror reflections and apparent depth refraction

Laboratory ten began with an investigation of the relationship between the distance of an image behind a mirror versus the distance of the object in front of a mirror.


Jessicalynn and Brian work out the image position.

In the second part the students worked on measuring the apparent depth of a penny under water versus the actual depth of the penny.


Norma peers into the small bucket, Corazon the larger bucket, Leilani is measuring.

The small blue bucket provides a nice intermediate depth between beakers and the Ace bucket, but the bottom is not at the bottom so to speak. A white flat-bottomed bucket of the same size would be better. Behind the Ace bucket are graduated cylinders that provide even more depth.

Sanolyn works with a 2000 ml graduated cylinder.

Monaliza indicates the apparent location of the penny image under water by looking in the top of the graduated cylinder. The cylinder keeps the viewing angle small. For small angles the ration of the actual depth to the apparent depth is effectively equivalent to the index of refraction. Eva records the data.
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