How Do You Calculate Vector Components in Physics?

[Rich52490]

http://img45.imageshack.us/img45/7585/physicspz0.th.jpg

Well I really have no idea where to begin with this one, if anyone could get me pointed in the right direction that would be much appreciated.

 

[Dschumanji]

Start out by finding the x and y components of the two vectors shown.

 

[Rich52490]

F1 = 120cos(60*) = 60
120sin(60*) = 103.9
x and y = (60,103.9)

F2 = -75cos(75*) or is it -75cos(15*)? = -19 or -72.4
75sin(75*) or 75sin(15*) = 72.4 or 19
x and y = (-19,72.4) or is is it (-72.4, 19)

 

[Dschumanji]

F1 = 120cos(60*) = 60
120sin(60*) = 103.9
x and y = (60,103.9)

F2 = -75cos(75*) or is it -75cos(15*)? = -19 or -72.4
75sin(75*) or 75sin(15*) = 72.4 or 19
x and y = (-19,72.4) or is is it (-72.4, 19)

Either angle (75* or 15*) would work, the problem arises when you apply the trig functions to find the components. For example, look at how the the cosine function is defined: cos(theta) = adj/hyp. In your second answer for the x component of F2, you are saying that the leg adjacent to the angle is on the x axis, when in reality it is along the y-axis according to the definition of cosine.