- #1
alex3
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Though I'd scan for ease ;)
Check the Pendulum question out http://dl.getdropbox.com/u/37461/physhelp/secC1.png and http://dl.getdropbox.com/u/37461/physhelp/secC2.png,and the http://dl.getdropbox.com/u/37461/physhelp/secB1.png.
Should all be in the scans.
See the http://dl.getdropbox.com/u/37461/physhelp/workings.png.
Aircraft question: a) seems to be obvious to me; traveling at 170km/h, needs to travel 300km. v = d/t, therefore t = d/v = 300/170 = 30/17 hours (no calculator allowed, left it in a fraction). As for b).. Drew a triangle, due north in an hour he should have traveled 170km, due 010 degrees he traveled 134km, but the question's five marks, and I can't think they expect us to know sin or cos of 10 or 80. The thing that really throws me on this question is that his speed is 'relative to the air'.
Pendulum: Got 2π\sqrt{\frac{r}{10}}, with r being the length of the pedulum. b) I got the same as a), but \frac{r}{15}. I was thrown on these two because the question said 'calculate', so I assume they want an actual integer, but I couldn't find a hint in the question to what r should be to substitute. c) was harder. Could not quite understand the question enough to answer it. d) seemed ok, I ended up with a messy fraction (right at the bottom of the workings scan) and thought I must have buggered up the algebra some where. e) would've probably have been fine if I got d).
I just need pointing in the right direction; it's more getting my head thinking along the right lines than getting the exact integer if required (though that'd be nice!) Thanks!
Homework Statement
Check the Pendulum question out http://dl.getdropbox.com/u/37461/physhelp/secC1.png and http://dl.getdropbox.com/u/37461/physhelp/secC2.png,and the http://dl.getdropbox.com/u/37461/physhelp/secB1.png.
Homework Equations
Should all be in the scans.
The Attempt at a Solution
See the http://dl.getdropbox.com/u/37461/physhelp/workings.png.
Aircraft question: a) seems to be obvious to me; traveling at 170km/h, needs to travel 300km. v = d/t, therefore t = d/v = 300/170 = 30/17 hours (no calculator allowed, left it in a fraction). As for b).. Drew a triangle, due north in an hour he should have traveled 170km, due 010 degrees he traveled 134km, but the question's five marks, and I can't think they expect us to know sin or cos of 10 or 80. The thing that really throws me on this question is that his speed is 'relative to the air'.
Pendulum: Got 2π\sqrt{\frac{r}{10}}, with r being the length of the pedulum. b) I got the same as a), but \frac{r}{15}. I was thrown on these two because the question said 'calculate', so I assume they want an actual integer, but I couldn't find a hint in the question to what r should be to substitute. c) was harder. Could not quite understand the question enough to answer it. d) seemed ok, I ended up with a messy fraction (right at the bottom of the workings scan) and thought I must have buggered up the algebra some where. e) would've probably have been fine if I got d).
I just need pointing in the right direction; it's more getting my head thinking along the right lines than getting the exact integer if required (though that'd be nice!) Thanks!
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