Principles Giancoli
Physics: with Applications, 6th Edition
53. (a) Note that sin 15.0o
100
0.259 and sin 15.5o 0.5o 100 3% 15.0o
0.267 .
sin sin
100
8 10
3
0.259
100
3%
(b) Note that sin 75.0o
0.966 and sin 75.5o
0.5
o
0.968 .
sin 100 2 10
3
100 0.2% 75.0o sin 0.966 A consequence of this result is that when using a protractor, and you have a fixed uncertainty in the angle ( 0.5o in this case), you should measure the angles from a reference line that gives a large angle measurement rather than a small one. Note above that the angles around 75o had only a 0.2% error in , sin while the angles around 15o had a 3% error in sin .
54. Utilize the fact that walking totally around the Earth along the meridian would trace out a circle whose full 360o would equal the circumference of the Earth.
100
100
0.7%
1 minute
1o 60 minute
2
6.38 103 km 360
o
0.621 m 1 km
1.15 mi
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