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Homework Statement
Which of the following are true?
A) A vect. prod. C=C vect. prod. A
B) The x-component of a vector can be +, -, or zero
C) If A=BxC and C=64i, then Ax=0
D) If A perp to B, then B dot A =0
E) The magnitude of a vector is sometimes negative.
F) The scalar (or dot) product of two vectors can be +, -, or zero.
Homework Equations
BxC = BC*cos(theta) where theta = angle between vectors
The Attempt at a Solution
Below are my attempts at proving or disproving each statements.
A) False: Using the right hand rule, the direction of the resulting product will be inverted when comparing AxC and CxA
B) True: A vector could cover horizontal distance to the right (positive), to the left (negative), or be a vertical vector with an x component of zero.
C) False: 64i could potentially result in an answer where Ax = 64i
D) True: BxA = BAcos(90) = BA*0 = 0
E) False: A magnitude is the absolute value of a vector and therefore can never be negative.
F) False: A scalar product must always be positive as all scalars are positive--they would be the absolute value of a vector.
I tried answering B & D as true and the rest false but this was not correct. I am not sure which statements I am confused on. I'm fairly confident of my answers to A, B, D, and E while a little less sure on C and F.
Thanks,
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