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Initially, the shape of the front resembles a Gaussian, with a wide sloping surface and flat top. As the experiment progresses, the frontal boundary gradually sinks relative to the free surface. Its sides flatten and the width of the center peak narrows (see Figure 4.2).
Using the equator for the deformation radius,
equation x, we calculate the predicted radius of deformation to be around 20 centimeters, or half of the width of the tank. Since the boundary of the front extends all the way to the outside of the tank, about 3/4 of the distance to the bottom of the tank, the actual radius of deformation for this front is slightly larger than this prediction. Therefore, we see the slope of the front decrease towards the edge of the tank, as it has no more room to spread outwards.
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