Which movement has the greatest net work done?

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The discussion centers on a question regarding which movement has the greatest net work done, with the original poster believing the answer is (D), while the answer key states (C). The poster argues that movements (A), (B), and (C) all result in zero net work due to constant speed indicating zero resultant force. There is a suggestion that the answer key may be incorrect, supported by a reference to a related physics forum discussion. The conversation emphasizes the importance of confirming the accuracy of the answer key in physics problems.
songoku
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Homework Statement
Please see below
Relevant Equations
W = F.d
1717897815283.png


My answer is (D) but the answer key is (C).

My reasoning is that the net work for (A), (B) and (C) are all zero since the object moves with constant speed so the resultant force is also zero. What is the mistake in my reasoning?

Thanks
 
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Have you considered the possibility that the answer key might be in error?
 
kuruman said:
Have you considered the possibility that the answer key might be in error?
Yes, but knowing me, it is better to ask for confirmation here.

Thank you very much kuruman
 
Thread 'Variable mass system : water sprayed into a moving container'

Thread 'Variable mass system : water sprayed into a moving container'

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Thread 'Minimum mass of a block'

Thread 'Minimum mass of a block'

Here we know that if block B is going to move up or just be at the verge of moving up ##Mg \sin \theta ## will act downwards and maximum static friction will act downwards ## \mu Mg \cos \theta ## Now what im confused by is how will we know " how quickly" block B reaches its maximum static friction value without any numbers, the suggested solution says that when block A is at its maximum extension, then block B will start to move up but with a certain set of values couldn't block A reach...
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