(b) the magnitude of the force during the given interval is 225.7 N.
(a) The acceleration of the salmon fish is 13.5 m/s²
The given parameters;
The distance traveled by the salmon fish when two-thirds of its length has left the surface;
[tex]s = \frac{2}{3} \times 1.5 \ m = 1 \ m[/tex]
(a) The acceleration of the salmon fish is calculated as;
[tex]v^2 = u^2 + 2as\\\\2as = v^2 - u^2\\\\a = \frac{v^2 - u^2}{2s} \\\\a = \frac{6^2 - 3^2}{2\times 1} \\\\a = 13.5 \ m/s^2[/tex]
(b) the magnitude of the force during the given interval is calculated as;
[tex]\Sigma F_y = F_{up} - F_{down}\\\\F = ma - mg\\\\F = m(a - g)\\\\F = 61 (13.5-9.8)\\\\F = 225.7\ N[/tex]
Thus, the magnitude of the force during the given interval is 225.7 N.
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