Question

Cross product of two paralle or antiparallel vectors is a null vector. Is this statement true or false?

Answer 1

Answer:

This statement is true because when two vectors are parallel or antiparallel, the angle between them is 0° (in the case of parallel) or 180° (in the case of antiparallel) and we know by the formula,

A×B = |A| |B| sin ¢

and the value of sin at 0° and 180° is 0.

So, the cross product will be a null vector.

Answer 2

This statement is true.

• As when we talk about the parallel and anti-parallel they make only two angles between them.
• One is 0° and the other is 180°.
• The formula is A×B=A·B sinФ
• For sin0=0 and sin 180=0
• So therefore whenever there is parallel then there product is zero.
• The another significance of it is that the cross product of them gives the curl of a vector function
• It defines the tendency to rotate about axis.
• Defines the axis of rotation and the strength of the rotation.