Physics 218 - Volume 1 - Mechanics Introduction Question

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SUMMARY

The discussion centers on the challenges faced by a student preparing for a comprehensive final exam in Physics 218, specifically focusing on Kinematics, the Work-Energy Theorem, Conservation of Energy, and Conservation of Momentum. The student expresses difficulty in understanding the line integral used to calculate work done by forces, as represented by the equation W = ∫(F · dr) from r1 to r2. Clarification is sought on how this integral relates to the total work and energy in joules, highlighting a need for deeper comprehension of the underlying physics concepts.

PREREQUISITES
  • Understanding of Kinematics principles
  • Familiarity with the Work-Energy Theorem
  • Knowledge of Conservation of Energy and Conservation of Momentum
  • Basic calculus, specifically integration and anti-derivatives
NEXT STEPS
  • Study the derivation and application of the Work-Energy Theorem
  • Learn about line integrals in the context of physics
  • Explore examples of calculating work done by variable forces
  • Review tutorials on Kinematics and energy conservation principles
USEFUL FOR

Students enrolled in introductory physics courses, particularly those preparing for exams in mechanics, as well as educators seeking to reinforce concepts related to work and energy.

lostdaytomorrow
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Hey there fellas, I just joined this board yesterday. I'm a "Vet" over at Bodybuilding.com, so I'm aware of how boards work, just so you understand I'm not just joining the site and making a new thread.
I've gone through all of the archives and read through the threads that seem to be about what I am learning in this course, F=ma, and the W.E.T. and Conserv. of Energy, and Conserv. of Momentum. So far, I haven't really found many threads that seem to have any relevance to what I am trying to learn. Our comprehensive final is worth 40% of our GPR so I plan on making this site my new home for the new 5 weeks or so for sure.
Now, after that great narrative, here is my conundrum (trying to sounds like a smart kid). The exam I will be taking this Wednesday will be mainly over Kinematics, Work-Energy Theorem, Conservation of Energy, and Conservation of Momentum. We don't get to any circular motion until after this exam. I am having a lot of trouble understand the line integral when defining the Work of the Forces on a particle. I have no idea how to put the equations in this post, so I will explain in as much detail as possible.
This is the equation I am having a difficult time grasping:
W(of the force, from r_1, to r_2) = the Integral(from r_1, to r_2) of the vect.Force * d(vect r)
I've seen in other threads that the "d*r" in that equation can be listed in several different ways, but this is the way it is in my text.
Is there any way someone could explain how this line integral is giving the total work?
I understand the KE and PE equations, where I just insert the knowns and solve for the unknowns.
I don't understand how taking the anti-derivative of a Force and then multiplying it by the distance the Force "went" is going to give me how many joules of Energy.
I apologize for such a long post, and if the answer is somewhere else, and I have missed it, just direct me to the correct place and no answer will be needed.
Thank you for your time.
-B.G.:confused:
 
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See https://www.physicsforums.com/showthread.php?t=8997" for instructions on how to generate formulas. Note, that due to a recent upgrade the perview function does not generate the equations. To see the result you must post your message. You can edit it for up to 24hrs after the inital post.

General questions are hard to answer, you may want to look through our tutorials for some helpful information.

Otherwise, post specific questions showing your work or at least your understanding of what you need to do.

Welcome to the Physicsforums.
 
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Integral said:
See https://www.physicsforums.com/showthread.php?t=8997" for instructions on how to generate formulas. Note, that due to a recent upgrade the perview function does not generate the equations. To see the result you must post your message. You can edit it for up to 24hrs after the inital post.
General questions are hard to answer, you may want to look through our tutorials for some helpful information.
Otherwise, post specific questions showing your work or at least your understanding of what you need to do.
Welcome to the Physicsforums.


Sounds great, thanks man.
 
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