Correct energy transformation about circuit with EMF, a resistor and a motor

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Homework Help Overview

The discussion revolves around energy transformations in a circuit involving an EMF source, a resistor, and a motor. Participants are analyzing different answer choices related to the energy transformations occurring in this setup.

Discussion Character

  • Conceptual clarification, Assumption checking, Mixed

Approaches and Questions Raised

  • Participants are exploring the differences between various answer choices, particularly focusing on the definitions and interpretations of mechanical energy, gravitational potential energy, and their roles in the context of the problem. Questions about the reasoning behind excluding certain options are raised.

Discussion Status

The conversation is ongoing, with participants expressing uncertainty about their answers and seeking clarification on the definitions of energy types. Some guidance has been offered regarding the definitions of mechanical energy, but no consensus has been reached on the correct answer.

Contextual Notes

Participants are navigating the constraints of homework rules that prevent direct answers from being provided, which influences the nature of the discussion and the questions being asked.

songoku
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Homework Statement
Please see below
Relevant Equations
Energy transformation
1694657801851.png


My answer is C (although I am not sure if the correct one is C or D). I suppose since the 1-V battery is being charged by the 9-V battery, the electrical energy should be on the RHS of the energy transformation. Am I correct?

Thanks
 
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Given that you think that the correct answer is C, why did you exclude answer A? What's the difference between A and C?
 
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kuruman said:
Given that you think that the correct answer is C, why did you exclude answer A? What's the difference between A and C?
Because the pulley lifts a load so I think there would be energy converted to GPE, which is not covered by option A

Thanks
 
What do you understand mechanical energy to be?

Hint: Read the first sentence here.
 
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kuruman said:
What do you understand mechanical energy to be?

Hint: Read the first sentence here.
I thought the mechanical energy in this case maybe refer to something in the motor or pulley (like rotation). Is it not? So the correct answer should be A?

Thanks
 
songoku said:
So the correct answer should be A?
Are you asking me or are you telling me? As you know, according to our rules we cannot give answers away.
 
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kuruman said:
Are you asking me or are you telling me? As you know, according to our rules we cannot give answers away.
I am asking, sorry.

My answer is still the same, it is C and the reasoning is this
songoku said:
I thought the mechanical energy in this case maybe refer to something in the motor or pulley (like rotation)
Is my reasoning not correct?

Thanks
 
songoku said:
I am asking, sorry.

My answer is still the same, it is C and the reasoning is this

Is my reasoning not correct?

Thanks
I believe if you are adhering to the definition, then gravitational potential is a part of mechanical energy. Do you have definitions given to you of mechanical energy that say otherwise?
 
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erobz said:
I believe if you are adhering to the definition, then gravitational potential is a part of mechanical energy. Do you have definitions given to you of mechanical energy that say otherwise?
No, I don't. What I learned about mechanical energy is that it is the sum of potential and kinetic energy. I am only using my own interpretation that maybe this is some trick question so I tried to include whatever rotation in motor and pulley to be referred as mechanical energy and gravitational energy is treated separately

Thanks
 
  • #10
`IMO none of the given answers are correct and the appropriate answer should be:
chemical → electrical → thermal + mechanical
 
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  • #11
Thank you very much for the help and explanation kuruman, erobz, Steve4Physics
 
  • #12
songoku said:
Thank you very much for the help and explanation kuruman, erobz, Steve4Physics
If you remember, let us know what the supposed correct answer was when you find out.
 
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