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

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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?
 
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.
 
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.
 
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?
 
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
 
`IMO none of the given answers are correct and the appropriate answer should be:
chemical → electrical → thermal + mechanical
 
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Thank you very much for the help and explanation kuruman, erobz, Steve4Physics
 
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.