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Direction of Vectors - a shot across the bows?


I've been looking over the deferred Physics paper from last year and noticed something in question7, on mechanics.


The question (shown here) asked students to calculate the resultant velocity of a swimmer who sets out to swim at 2.5 m/s at right angles to a current of 4 m/s.


All standard stuff. But I noticed that the question did not ask the student to find the magnitude of the resultant velocity, it just said 'velocity'


Now, I might be wrong in this, but I think it's quite some time since students were asked to find the direction of a resultant vector from vector analysis, as well as its magnitude. The direction of, say, a centripetal acceleration, is frequently required, or a force. But questions that required the use of trigonometry have often been phrased to avoid the issue of direction, or the marking scheme is structured so that there was no penalty for those who didn't mention it. But I checked the marking scheme, and sure enough there were 3 marks for the magnitude - and 3 marks for the direction:


Fair enough. It was always on the syllabus. But I wonder if it reflects the thinking of whoever it is that set the questions for this summer's exam.....



(Deferred papers were introduced last summer for the first time. They are used for a very small number of students who are unable to sit the summer exam and who satisfy very tight criteria. They are available on the examinations.ie website, but in a separate subsection to the regular papers: State Examination Commission - Exam Material Archive (examinations.ie))






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