Impossible Question in CIE Physics Exam: Is It Really Unsolvable?

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A recent CIE physics exam included a question deemed impossible by students, particularly part (c), which lacks a clear solution path. Participants discussed the potential to express the current in lamp Y as a function of its resistance, but the question's requirement for a numerical answer raises concerns. There is skepticism about the exam's integrity, given the expectation for students to provide straightforward calculations at this level. The community is awaiting the mark scheme and examiner's report for clarification on the question's validity. This situation highlights ongoing debates about exam quality and fairness in standardized testing.
skyglow1
Hi, the students that are the year below my year level sat their external physics exam recently. Only problem was, there seems to be an impossible question in the paper:

http://img.photobucket.com/albums/v221/skyglow1/impossibleq.jpg

This is a scan from the paper. It seems like there's no way you can do part (c) of the question. This is from CIE examinations so I find it very hard to believe they could have made such a massive mistake.
 
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Well, you can always say something like:

Current in lamp Y = 12V/ R_Y or so, no ?

It doesn't mean that you cannot do the last exercise.
 
vanesch said:
Well, you can always say something like:

Current in lamp Y = 12V/ R_Y or so, no ?

It doesn't mean that you cannot do the last exercise.

That was what I was thinking too, but it says calculate so I'm inclined to think its a numerical answer instead of interms of R_Y. And at this level you wouldn't be expected to say something like "Let R_Y be the resistance of lamp Y, then I = 12/R_Y".
 
I agree. I didn't realize you meant this was a real exam today - I was about to look up the markscheme online. it will be interesting to see what it (and the examiners report) contains, when it eventually appears.
 
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