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kooaznboi1088
Jan15-06, 09:08 PM
Hey I have this question about vectors that I can't solve. Can someone explain it to me?

Vector A is 1550 25 degrees North of East. Vector B is 41 East of South. Vector C was 35 North of West. A+B+C=0. Find B and C.

stunner5000pt
Jan15-06, 09:19 PM
break your vectors into components when you add up your X and Y components (SEPARATELY) of all teh vectors you should get zero.

kooaznboi1088
Jan15-06, 09:21 PM
Thats the problem I got

1550sin 25 +Ysin 35-xsin49=1550cos25-Ycos35+Xcos49

but I get like 5000 and 6000 for values of X and Y....

stunner5000pt
Jan15-06, 09:29 PM
who are X and Y. Can you use B and C like you use in your question please

also you havent got ALL the signs correct.
Assume a specific coordinate system with either up or down to be positive and left or right to be positive

kooaznboi1088
Jan15-06, 09:39 PM
sorry, im just too used to using X and Y, Ok B and C it is.
Assuming Up and Right is Positive and Left and Down is negative.
Vector A, being 25 N of E, would be in the 1st quadrant and so both its components are positive.
Vector B woudl be in the 4th quadrant. So its Y values would be negative and X values would be positive.
vector C woudl be in the 2nd quadrant so its X compment woudl be negative and Y component woudl be positive.

1550sin 25 + Csin 35- Bsin49=1550cos25 - Ccos35 + Bcos49=0

stunner5000pt
Jan15-06, 09:44 PM
ok now you can get two equations from that equality... solve or B and C like simulatenous equations

Your answers have to be right... if you do the math correctly

kooaznboi1088
Jan15-06, 09:55 PM
no i get B=5548.6 and C=6158

kooaznboi1088
Jan15-06, 10:46 PM
do es any1 get a different results when doing the math? I like triple checkd this