Reflection and Refraction

Laboratory eleven began with placing a one dollar coin on top of a towel and under a beaker filled with water. The top of the beaker was covered with a ceramic floor tile. I then asked the class to come up and determine what coin was under the bottom of the beaker.

Due to total internal reflection at the bottom, and refraction at the sides of the beaker, the coin is invisible.

Then I put the coin in an empty dish basin at a distance of four meters. No one could see the coin: the side of the dishpan blocked their view.


Then I filled the dishpan with water, and the students could now see the coin. This led to an explanation of apparent depth

Ariel Maylea and Alden set up to measure the depth of the penny tallest of the graduated cylinders.

 
Moses and Gorang determine the apparent depth of the penny in the tallest cylinder. This term again I lined up the cylinders from shortest to tallest on the middle table.


The board notes on the "index of reflection" portion of the laboratory. I opted to use the parallel terminology "index of refraction" and "index of reflection" to make clear the distinction between the two slopes.


Connie and Mindira work on the object and image position of a space alien figure.

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