alleryWhich statement about a null vector is correct?
AIts direction is fixed along the positive x-axis
BIts dot product with any vector is always zero
CAdding it to a vector reverses the vector
DIts cross product with any vector gives a scalar
Answer & Solution
Correct answer: B. Its dot product with any vector is always zero
A null vector has zero magnitude and arbitrary direction.
The notes state that its dot product with any vector is zero, and its cross product with any vector is also a null vector.
Adding or subtracting it leaves the original vector unchanged.
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