Salmon often jump waterfalls to reach their
breeding grounds.
Starting downstream, 2.45 m away from a
waterfall 0.373 m in height, at what minimum
speed must a salmon jumping at an angle of
42.5
â—¦
leave the water to continue upstream?
The acceleration due to gravity is 9.81 m/s
2
.
Answer in units of m

Respuesta :

Answer:

5.38 m/s

Explanation:

Given (in the x direction):

Δx = 2.45 m

v₀ = v cos 42.5°

a = 0 m/s²

Δx = v₀ t + ½ at²

(2.45 m) = (v cos 42.5°) t + ½ (0 m/s²) t²

2.45 = (v cos 42.5°) t

t = 3.32 / v

Given (in the y direction):

Δy = 0.373 m

v₀ = v sin 42.5°

a = -9.8 m/s²

Δx = v₀ t + ½ at²

(0.373 m) = (v sin 42.5°) t + ½ (-9.81 m/s²) t²

0.373 = (v sin 42.5°) t − 4.905 t²

0.373 = (v sin 42.5°) (3.32 / v) − 4.905 (3.32 / v)²

0.373 = 2.25 − 54.2 / v²

v = 5.38

Graph:

desmos.com/calculator/5n30oxqmuu