Negative vector why isn't it choice 4.

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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

 

[UncertaintyAjay]

What does it mean for magnitude to be negative? Does it make sense for the length of a vector to be negative?

 

[bigcookie]

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.

 

[UncertaintyAjay]

It would be -120. Not -60

 

[bigcookie]

Super clear ... thank you very much for your help.