Respuesta :
Let the salmon jump with speed v at an angle of 33.3 degree
So here we can find out the components of his velocity in x and y direction
[tex]v_x = v cos33.2[/tex]
[tex]v_y = v sin33.2[/tex]
now the horizontal displacement of the salmon is 3.15 m so he cover this horizontal distance with constant speed as there is no acceleration in x direction
here we can say
[tex]v_x * t = 3.15[/tex]
[tex]v cos33.2 * t = 3.15[/tex]
[tex]v*t = 3.76[/tex]
now in Y direction it is an accelerated motion as it is accelerated due to gravity
[tex]y = v_y * t + \frac{1}{2}at^2[/tex]
[tex]-0.45 = v sin33.2* t - \frac{1}{2}*9.8* t^2[/tex]
now we will plug in v*t = 3.76
[tex]-0.45 = 3.76 * sin33.2 - 4.9 * t^2[/tex]
[tex]4.9 t^2 = 2.51[/tex]
[tex]t^2 = 0.512[/tex]
[tex]t = 0.72 s[/tex]
now speed v is given by equation above
[tex]v*t = 3.76[/tex]
[tex]v*0.72 = 3.76[/tex]
[tex]v = 5.25 m/s[/tex]
so here he must have to jump with minimum speed of 5.25 m/s
