Circ Basin

Failed to parse (SVG with PNG fallback (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://en.wikipedia.org/api/rest_v1/":): {\displaystyle \eta = \left{ \begin{array}{cc} \frac{W x_1 x_2}{2ghR} & f_c=0 \\ \frac{W f_c}{Rgh\kappa} \left[ \frac{R^2}{8} + \frac{1}{4}\left(\frac{2\kappa x_1 x_2}{f_c}-x_1^2-x_2^2\right) \right] & f_c \neq 0 \right. | }

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