Question

The resultant of $\vec{A}\times 0$ will be equal to

• A. zero
• B. A
• C. zero vector
• D. unit vector

Answer 1

Answer: (C)

The cross product $\vec{A}\times \vec{B}$ is a vector, with its direction perpendicular to both $\vec{A}$ and $\vec{B}.\vec{A}\times \vec{B}$ is area. If side $B$ is zero, area is zero.
$\vec{A}\times 0$ is a zero vector.
If in case $0$ is a scalar, then also the product is zero.
But a scalar $\times$ a vector is also a vector.
Hence one gets a zero vector in any case.