Negative vector why isn't it choice 4.

AI Thread Summary
The discussion centers on the properties of vector B, which has a magnitude of 45.0 m and an angle of 60.0 degrees with the +x axis. The negative vector -B has the same magnitude of 45.0 m but points in the opposite direction, making its angle effectively -120 degrees with respect to the +x axis. Participants clarify that magnitude cannot be negative, emphasizing that the direction is what changes when considering the negative vector. The confusion arises from interpreting the angle and direction after negating the vector. Ultimately, the consensus is that the negative vector's angle should be -120 degrees, not -60 degrees.
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Homework Statement



If the vector B⃗ has a magnitude of 45.0 m and makes an angle of 60.0 ∘ with the +x axis, the vector -B⃗
choices:
1. has a magnitude of 45.0 m
2. has the same direction as B⃗ , but a magnitude of − 45.0 m
3.makes an angle of − 60.0 ∘ with the +x axis
4. has the opposite direction of B⃗ and a magnitude of − 45.0 m

Homework Equations

The Attempt at a Solution


y axises
I -------45.0m diagonal
I 60 Degrees angle
<-(-x)-------------------+x--axises---->
I
I
-y axises
 
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What does it mean for magnitude to be negative? Does it make sense for the length of a vector to be negative?
 
Oh . I see. Thanks you . Magnitude can't be negative
So is it -60 with respect to the x causes because it's now in the third quadrant since the vector b negative is when you reverse the head and the tail of the arrow.
 
It would be -120. Not -60
 
Super clear ... thank you very much for your help.
 
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