ATAR Notes: Forum
VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Physics => Topic started by: soopertaco on June 07, 2011, 01:57:43 pm
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I don't really know how consistent trial exams are with sig figs, but this is getting out of hand, i keep getting questions wrong just because of sig figs.
anyone care to share any tips on how they express answers?
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I don't really know how consistent trial exams are with sig figs, but this is getting out of hand, i keep getting questions wrong just because of sig figs.
anyone care to share any tips on how they express answers?
I don't think sig figs actually matter that much in physics (Sure they do in chem, but this is physics :P). As my teacher said, "the more decimal places, the better". For example, if the values I've been given are to 2 decimal places, I'll write my answer to 3 decimal places.
I wouldn't worry about sig figs in the exam, I'd be more worried about making sure I get every question right before I went into technicalities such as this.
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I don't think sig figs actually matter that much in physics (Sure they do in chem, but this is physics :P). As my teacher said, "the more decimal places, the better". For example, if the values I've been given are to 2 decimal places, I'll write my answer to 3 decimal places.
I wouldn't worry about sig figs in the exam, I'd be more worried about making sure I get every question right before I went into technicalities such as this.
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I don't really know how consistent trial exams are with sig figs, but this is getting out of hand, i keep getting questions wrong just because of sig figs.
anyone care to share any tips on how they express answers?
Being both a chem and physics student, if I was given 2 decimal places to start with I would NEVER throw back 3.
As far as sig figures are concerned in physics I think they only come into play with large numbers where they get you to write 125,000 as 1.25 * 10^5... I have found that trial exams for physics overall are not very consistent with significant figures, but I would try not to give an answer to more decimal places than you begin with...
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@thattricksta sometimes i would be given something like 50 metres as my lowest sig fig and then i would get something like 1250 N in the answers they would stay at 1250 N this is VCAA btw but the numbers aren't off the top of my head.
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@thattricksta sometimes i would be given something like 50 metres as my lowest sig fig and then i would get something like 1250 N in the answers they would stay at 1250 N this is VCAA btw but the numbers aren't off the top of my head.
Wow the quote warp up before was messed... hopefully you got the part from me
"Being both a chem and physics student, if I was given 2 decimal places to start with I would NEVER throw back 3.
As far as sig figures are concerned in physics I think they only come into play with large numbers where they get you to write 125,000 as 1.25 * 10^5... I have found that trial exams for physics overall are not very consistent with significant figures, but I would try not to give an answer to more decimal places than you begin with..."
I think as far as physics is concerned, I wouldn't worry so much about significant figures but rather decimal points... I'm not sure how wise it would be to give an answer to 3 decimal points if the maximum you start with is 1.
Thats probably the only thing I could think of
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In the recent trials I have done, I tend to round off my values to the amount of sig figs the questions asks?
As in find the Initial momentum of a 78.50kg man who is running at a speed of 6.37ms
p=mv = 75.50x6.37=510kgms
^^ In the question the values are given in 2 sig form thus I give my answer in 2 sig form, it looks more consistent.
Hope I helped a little.
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p=mv = 75.50x6.37=510kgms
^^ In the question the values are given in 2 sig form thus I give my answer in 2 sig form, it looks more consistent.
Yeah, that's what my teacher told us to do.
It's to do with how you can only be as accurate as the data you are provided with. I think that's the reason we use significant figures (as well as to save time writing out ridiculously long numbers)
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Do u actually lose marks for putting in 1700 instead of 1.7 x 10^3??
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Do u actually lose marks for putting in 1700 instead of 1.7 x 10^3??
If your question started with less than 4 significant figures it would be fair to take off a mark.