# Can Vectors with an angle 180(degrees+) have a negative magnitude?

by SaltyBriefs
Tags: components, homework, signs, trigonometry, vectors
 P: 10 1. The problem statement, all variables and given/known data Can vectors with 180+(degrees) have a negative magnitude? I'm trying to find components of a vector that is going 260 km, 48 (degrees) south of east. So I'm confused whether the 260 is positive or not because of the -48 degrees. 2. Relevant equations ($\vec{V}$) (sin$\theta$) ($\vec{V}$) (cos$\theta$) 3. The attempt at a solution (-260km)(sin(48)) or (260km)(sin(48)) =$\vec{V}$$_{y}$ (-260km)(cos(48)) or (260km)(cos(48)) =$\vec{V}$$_{x}$ Which one??
 P: 140 sin(x) = -sin(-x) cos(x) = cos(-x) Hope that helps. Just use the convention that counterclockwise is postive and clockwise is negative in terms of measuring an angle.
P: 10
 Quote by WatermelonPig sin(x) = -sin(-x) cos(x) = cos(-x) Hope that helps. Just use the convention that counterclockwise is postive and clockwise is negative in terms of measuring an angle.
Thank you this helped so much! But um just a quick question, why is sin negative? O.o

P: 10

## Can Vectors with an angle 180(degrees+) have a negative magnitude?

 Quote by SaltyBriefs Thank you this helped so much! But um just a quick question, why is sin negative? O.o
Oh wait is this from cos, sin
and since it is in the 4th quadrant, y is negative (sin) and x is positive (cos)

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