Question

Salmon often jump waterfalls to reach their breeding grounds. Starting downstream, 1.84 m away from a waterfall 0.251 m in height, at what minimum speed must a salmon jumping at an angle of 38.3 ◦ leave the water to continue upstream? The acceleration due to gravity is 9.81 m/s 2 .

Answer 1

Answer:

4.73 m/s

Explanation:

R=1.84  m

H=0.251 m

∅=38.3°

For Horizontal Motion

aₓ=0      uₓ=ucos∅

x=uₓt+$\frac{1axt^{2} }{2}$

R=ucos∅*t+0

1.84=ucos(38.3)*t

t=$\frac{2.344}{u}$

For Vertical Motion

Y=Uy*t+$\frac{1ayt^{2} }{2}$

By putting value

0.251=usin∅($\frac{2.344}{u}$)-($\frac{1}{2}g *(\frac{2.344}{u} )^{2}$)

0.251=sin(38.3)($\frac{2.344}$)-($\frac{1}{2}g *(\frac{2.344}{u} )^{2}$)

0.251=1.452-$\frac{83.057}{u^{2} }$

u²=22.41

u=4.73 m/s