Easy problem still wrong answer

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The discussion revolves around calculating the work needed to move a proton between two electric potentials, specifically from +630V to -60V. The initial calculation using the formula (Va-Vb)=Wba/q yields a result of Wba = -1.104 x 10^-16 J, which is correct based on the equation. However, confusion arises regarding the sign of the answer, as it depends on whether the work is done by the electric field or an external force. Participants express frustration over the ambiguity of the problem and the challenge of dealing with negative signs in physics calculations. The conversation highlights the common struggle with interpreting signs in work-energy problems.
melissa_y
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How much work is needed to move a proton from a point with a potential of +630V to a point where it is -60.0V?

Ok so wouldn't I just use the equation:

(Va-Vb)=Wba/q
(-60-630)=Wba/(1.6 x 10^-19)
Wba=-1.104 x 10^-16 J
 
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Your equation looks fine to me. What's the answer you expected?
 
Wba=-1.104 x 10^-16 J

But i keep entering it into the CAPA and it says wrong answer...
 
Try it without the negative sign.

The question is ambiguous, since it doesn't specify who or what is doing the work. If it's the electric field, then the answer is negative. If it's an external force, the answer is positive.
 
haha i love problems that are so simple yet you don't get an answer. Makes me start pounding on walls. Something simple has obviously gone unnoticed or like someone said, a negative sign is probably missing. Those negative signs piss me off to no end. Everytime i learn something where I am told the answer is always positive, i go to church for 40 hours straight to thank god for all the good he has done in the world such as the current subject i was just taught.

I truly hate negatives...
 

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