Suppose you walk 15 m in a direction exactly 25° south of west then you walk 22.5 m in a direction exactly 45° west of north. What is the angle of the compass direction of a line connecting your starting point to your final position measured South of West in degrees? Repeat part (a) by finding your distance from the starting point in m, but reverse the order of the two legs of the walk. That is, you first walk leg B, which is 22.5 m in a direction exactly 45° west of north, and then leg A, which is 15 in a direction exactly 25° south of west. What is the angle of the compass direction o
*What is the angle of the compass direction of a line connecting your starting point to your final position measured South of West in degrees?
I keep getting an angle of either 342 degrees or 162 degrees, one of which is east of south and the other is west of north... @LastDayWork
OOH, I know what I screwed up on. Ok @jhc2014 are you familiar with vectors/ vector components?
Write the two steps as vectors (in polar form).
not to familiar and not sure what polar form is
|dw:1392271434007:dw|
how would you get the angle of the compass from that? what formula would you have to use
ok, you'll have to break the vectors into their x and y components
that be 22.5cos(45)+15cos(25) for x right and 22.5sin(45)+15sin(25) for y right ?
you're VERY close
ok, first, for the x-axis, if you're right of the y-axis, then your numbers are positive, if you're on the left, the numbers are negative second, the angles 25 and 45 that you're given are relative. you have to start from the horizontal for your angles. so for example, the first vector that is "25". That starts from the negative x-axis. You need to add 180 so that you start from the positive x-axis. So the two questions you need to ask are: Is the vector component positive or negative? How do I modify the angles so that they include the FULL angle?
In my explanation, I didn't include the y-component. I want to see if you can figure that out.
y component=22.5sin(45)+15sin(205)?
-15 sin(205) +22.5 sin (90 + 45)
good attempt though. Does that make sense?
yes the angle is the vector itself right
ok so now you have your x and y to get your new angle tan^-1 (y/x)
41.7 degrees
never mind i made a calculation error -84.1 degrees?
x-component: 29.505 y=component 22.249
Your components are off
37.01905419 my x component was wrong
having the angle how would you find the distance from the starting point in meters but reverse the order of the two legs of the walk. That is, you first walk leg B, which is 22.5 m in a direction exactly 45° west of north, and then leg A, which is 15 in a direction exactly 25° south of west.?
use the pythagorean theorem
you should get 36.95 right
yes
when i went to put it in it said it was wrong
in what?
my online homework site
were ALL the answers wrong?
no the other ones were right
so just the length of the reverse?
yes
is this due immediately? I'm trying to figure out what we did wrong...
no not immediately
to be honest i have no idea why the Pythagorean therom didnt work
maybe sig figs?
i tried sigfigs but used my last attempt and the right answer was 31.02 so we were really close but i appreciate all the help youve given me wouldnt have been able to get it done without you thank you
oh, you only had a fixed number of tries?? I'm sorry
its not problem still got the others right no problem at all thanks again
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