Ripple Tank - Leo Rosin

 The construction and utilization of the ripple tank was an interesting task that was filled with a myriad of problems and cool demos

On the first Friday, we ordered the stuff for our demonstrations, I ordered a 24 in by 24 in clear acrylic sheet for the base of the ripple tank, a 2x4 24in long block of wood for the paddle, some 1/4in plastic tubes to serve as legs, a motor to move the paddle, and some polystyrene to use for the sides of the tank.

On Monday I set about assembling the tank but forgot duct tape and superglue so I helped other people with their projects. On Tuesday I cut the polystyrene sheet into 24inx2in tall strips to serve as walls, I then used tape and superglue to attach them to the rim of the acrylic sheet. I decided to ditch the legs as they were too thin and instead duct-taped the tank to four stools. I used PVC pipe to create an arm to hang the paddle off of and took the paddle home to shorten it somewhat. On Wednesday I set up the paddle with the motor and put it on the arm. I tested the tank and put water in it but there were multiple leaks and I had to empty it and try and seal up the cracks. On Thursday when I filled the tank with water the amount of leaks had decreased so I turned on the motor and hung the light over the bar to see the wave patterns on the floor. I also raised the paddle and taped 2 pencil tips to the bottom to create a circular ripple pattern.

 

On Friday I got the photos for our J-Term Demonstration. I got photos of Circular waves, Planar Waves, Constructive and Destructive Interference, Diffraction, and Reflection. 

Circular Waves occur when two points interact with the water. Planar Waves occur when a single bar creates a wave line. Constructive Interference occurs when two waves with positive amplitude meet and results in the two amplitudes of the waves adding together. Destructive Interference occurs when a wave positive amplitude and a wave with a negative amplitude meet which results in a both of the values being added together. Diffraction occurs when a small gap is provided for the waves to go through. The waves then emit from the gap in a semicircle pattern.

Reflection occurs when waves are sent towards an obstruction. The waves then ‘wrap-around’ the obstacle and propagate along the line due to the law of reflection
The Ripple Tank helps demonstrate multiple properties of waves in a cool and interesting way. 

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