How High Can a Salmon Jump Using Its Maximum Speed?

  • Thread starter Touchme
  • Start date
In summary, the conversation discusses a problem involving a Chinook Salmon and its ability to swim upstream past a waterfall. The salmon has a maximum underwater speed and jumping speed, and it can swim up a waterfall if the water speed is below a certain value. The question asks for the maximum height of the waterfall that the salmon can clear if it jumps vertically upwards from the base of the fall. Through calculations, the distance below the ledge where the water reaches a speed of 3.00 m/s is determined, and this value is added to the jumping height to find the answer.
  • #1
Touchme
41
0
salmon motion problem

Hi,

A Chinook Salmon has a maximum underwater speed of 3.58 m/s, but it can jump out of water with a speed of 6.68 m/s. to move upstream past a waterfall, the salmon does not need to jump to the top of the fall, but only to a point in the fall where the water speed is less than 3.58 m/s; it can then swim up the fall for the remaining distance. Because the salmon must make forward progress in the water, let's assume that it can swim to the top if the water speed is 3.00 m/s. If water has a speed of 1.40 m/s as it passes over a ledge, how far below the ledge will the water be moving with a speed of 3.00 m/s? (Note that water undergoes projectile motion once it leaves the ledge.)

If the salmon is able to jump vertically upward from the base of the fall, what is the maximum height of waterfall that the salmon can clear?

I tried using 6.68 as initial velocity, determine the time when it reaches max height (final velocity = 0). I use the time, initial velocity, and 9.8 to solve for the max height. The answer i got was 2.2766 m and its wrong. Can someone help me with this problem. Thank you
 
Last edited:
Physics news on Phys.org
  • #2
The waterfall is parabolic motion of "pieces" of water. I assume that a piece of water leaves the ledge horizontally with a speed of 1.40 m/s. As this piece of water travels along a parbolic path its speed increases. You need to calculate the vertical distance below the ledge where such a piece of water reaches a speed of 3.00 m/s. The salmon need to be able to jump up to this point in order to swim the remaining distance up to the ledge. Note that the answer asks the height of the ledge above the point where the salmon leaves the stream while jumping up to this point in the waterfall. So the answer is the sum of these two distances - jumping height and distance below ledge.
 
  • #3
Thank you for clarifying what the question is asking for and thanks for the tip.
 
  • #4
Remember that the speed of a projectile is determined by its both its velocity components.
 
  • #5
so how do u do part b- If the salmon is able to jump vertically upward from the base of the fall, what is the maximum height of waterfall that the salmon can clear?? I can't get it right
 
  • #6
What have you been able to determine thus far?

The maximum jumping height? What do you get for this distance?

The distance below the ledge where the water reaches a speed of 3.00 m/s?
 
  • #7
I got the distance below the ledge= .3 m
 
  • #8
help please for part b
 
  • #9
The values are to three significant digits in the problem. So please give your answers to the same. I get a slightly different value for the below the ledge distance. How did you get to your answer?

Do you have a problem in calculating the maximum jumping height of the salmon? To reach the point where the water speed is 3.00 m/s he will launch himself out of the water with a speed of 6.68 m/s and his speed at the top of his jump will be zero. What is his jumping height then?
 

FAQ: How High Can a Salmon Jump Using Its Maximum Speed?

1. What is the salmon problem?

The salmon problem refers to the declining population of salmon in various bodies of water around the world. This is often due to overfishing, habitat destruction, pollution, and climate change.

2. How does the salmon problem affect the environment?

The salmon problem has a significant impact on the environment. Salmon are a crucial part of the food web and their decline can disrupt the balance of ecosystems. It can also affect other species that rely on salmon for food, as well as the health of rivers and streams where salmon spawn.

3. What are some solutions to the salmon problem?

There are several solutions to the salmon problem, including implementing sustainable fishing practices, protecting and restoring salmon habitats, reducing pollution, and addressing climate change. Additionally, collaborations between governments, scientists, and local communities can also help in finding effective solutions.

4. How can individuals help with the salmon problem?

Individuals can contribute to solving the salmon problem by making sustainable seafood choices, reducing their carbon footprint, supporting organizations that work towards protecting salmon habitats, and raising awareness about the issue among their communities.

5. What is the role of scientists in addressing the salmon problem?

Scientists play a critical role in addressing the salmon problem. They conduct research to better understand the causes and effects of declining salmon populations, develop conservation strategies, and advise policymakers on effective solutions. They also work with communities and stakeholders to implement sustainable practices and monitor the health of salmon populations over time.

Back
Top