Attempted Part I & II Problems

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In summary, the conversation is discussing a problem with two parts, where the first part involves finding the value of x and the second part involves a projectile motion problem with no air resistance. The speaker is having trouble with the second part and is overthinking it, but is then reminded that it is a simple projectile motion problem with no air resistance. The conversation also mentions a difficulty with evaluating an integral and setting a variable to zero.
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theredbarronmvr
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Homework Statement
A bullet of mass m is shot vertically up with initial speed v0. It is subject to air resistance that is quadratic in speed (constant of proportionality c2).

i. What is the maximum height reached?

ii. What initial speed u0, would be necessary to reach the same maximum height in the absence of air resistance?

Express your answers in terms of c2, g, m, and v0.
Relevant Equations
For part i: m(dv/dt) = -c2(v^2) - mg
I have an attempted solution to part i here. I'm primarily having trouble with part ii since I don't see how the x found in part i can be attained if there's no air resistance term.
 

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theredbarronmvr said:
I'm primarily having trouble with part ii since I don't see how the x found in part i can be attained if there's no air resistance term.
If there is no air resistance, then it's a simple projectile motion problem.
 
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  • #3
PeroK said:
If there is no air resistance, then it's a simple projectile motion problem.
Ahh of course, thank you! I was definitely overthinking it.
 
  • #4
theredbarronmvr said:
I have an attempted solution to part i here. I'm primarily having trouble with part ii since I don't see how the x found in part i can be attained if there's no air resistance term.
In case you're wondering, when you evaluated the integral, you assumed ##c_2 \ne 0##, so it isn't valid to set ##c_2=0## in the expression you derived. (I assume that's the difficulty you were running into.) You have to set ##c_2## to 0 before you integrate.
 
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FAQ: Attempted Part I & II Problems

1. What is the purpose of attempting Part I & II problems in a scientific experiment?

The purpose of attempting Part I & II problems is to test and analyze the data collected in an experiment, in order to draw conclusions and make scientific claims. This allows for a deeper understanding of the experiment and its results.

2. How do you approach solving attempted Part I & II problems?

When solving attempted Part I & II problems, it is important to carefully read and understand the problem, identify the relevant data and variables, and use appropriate mathematical and scientific principles to solve the problem. It may also be helpful to break the problem down into smaller, more manageable steps.

3. What are some common mistakes to avoid when attempting Part I & II problems?

Some common mistakes to avoid when attempting Part I & II problems include using incorrect units, misinterpreting data, and making calculation errors. It is important to double check all calculations and to carefully consider the given data and its implications before solving the problem.

4. How do attempted Part I & II problems contribute to the overall scientific process?

Attempted Part I & II problems play a crucial role in the scientific process by allowing scientists to test and validate their hypotheses and theories. They also help to refine and improve experimental methods and contribute to the body of scientific knowledge.

5. Can attempted Part I & II problems have multiple solutions?

Yes, attempted Part I & II problems can have multiple solutions depending on the approach and assumptions made by the scientist. It is important to carefully consider the validity and implications of each solution before drawing conclusions from the data.

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