(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Salmon often jum waterfalls to reach their breeding grounds.

The acceleration of gravity is 9.81 m/s^2

Starting 1.73 m from a waterfall .0386 m in height, at what minimum speed must a salmon jumping at an angle of 44.3 degrees leave the water to continue upstream? Answer in units of m/s.

2. Relevant equations

Vox = Vocos(theta)

Vox = 6.179cos(44.3) = 4.42

Voy = Vosin(theta)

Voy = 6.179sin(44.3) = 4.316

3. The attempt at a solution

- I drew a graph:

x-axis labeled as 1.73m and the y-axis labeled as .386m

- Tried to find time:

t = (sqrt) 2(h)/g

t = (sqrt) 2(.386)/9.81

t = .28 seconds <-- I think this may be wrong.

- Tried to find Vo:

Vo = x/t

Vo = 1.73/.28

Vo = 6.179

Now plugged Vo result to find components:

Vox = Vocos(theta)

Vox = (6.179)cos(44.3)

Vox = 4.42

Voy = Vosin(theta)

Voy = (6.179)sin(44.3)

Voy = 4.316

... I'm not sure what to do next. Am I supposed to use the Pythagorean Theorem? And find the tangent? I have no clue. All help would be appreciated. =)

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# Homework Help: 2D Projectile Motion - Minimum Speed

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