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I have a n opinion, too. It's your assignment, so what is your answer? Then let's compare and discuss both views.
OK, I will go out on a limb and say that I think that it is a terrible exam question.
I have a feeling that it is probably mislabeled. What is marked as the transistor should be marked as a bulb - and what is marked as the bulb should be labeled as a resistor.
If mislabeling is not the case then there are other issues:
- The orientation of the transistor is not clear. I assume that the circuit is connected through the collector and emitter, but which is which? and does that even matter if nothing is connected to the base?
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Herschel Peeler
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Keep it simple. It is a basic class. Turning on the switch makes the light go out. (And blows up the transistor?)
Bad example of a question.
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Assuming the diagram really shows a transistor at the right, it is impossible to predict the behaviour since the transistor is incompletely wired. It could be on, off or partially conducting. Without knowing this, the "answer is unclear based on the diagram".
What matters, however, is that a technician or engineer not only needs to be able to analyze a functional circuit, he/she should also be able to tell when the information at hand is insufficient or incomplete. And he/she should know what is missing and where to get the missing parts. Only then wil he/she be able to analyze and possibly correct a circuit.
I disagree - or at least I can't fully agree. I'm with you in that the diagram is bad. It really should show the symbol for a bulb instead of a resistor, but that's irrelevant with respect to the question.
What matters, however, is that a technician or engineer not only needs to be able to analyze a functional circuit, he/she should also be able to tell when the information at hand is insufficient or incomplete. And he/she should know what is missing and where to get the missing parts. Only then wil he/she be able to analyze and possibly correct a circuit.
This is an actual question in a test.
So I guess you are saying that it is a bad question for a basic electronics class?
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The schematic diagram is bad. The question not, see post #7.
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If the schematic forms part of the question, and especially if the annotations are not on it, you should either mark it as correct for any and all answers (including no answer), or remove it from the exam and adjust the marks as if there was one fewer question.
I would also feel sympathy for any student who spent too much time trying to answer, or was rattled by the question and performed more poorly on the remainder of the test than they might otherwise have.
whatever you do, the final answer (undetermined) should not be marked as wrong. However, since either the symbols or the labels are wrong, if one were to make an assumption that the symbols were drawn correctly, then the answers miss the option "none of the above".
this is one of those perfect questions for statistics analysis. Does the pattern of answers given by a body of students correlate with their final mark, I.e. Does this question actually tell you something about what you want to find out? Any question that doesn't either (arguably) shouldn't be in the exam OR was not adequately taught.
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That assumes the annotations are wrong, that the battery voltage is suitable for the lamp, that the resistor value is high enough to keep the lamp looking "off", and that the switch can carry the required current.
ignoring the last one, they are all reasonable enough to consider when addressing a question such as this. It's not the most wrong answer, but I wouldn't mark the examiner correct (unless there were multiple accepted answers including "none of the above").
