What is the magnitude of resultant of cross product of two parallel vectors and ?

Option (3)

CONCEPT:

• Vector Product: It is also known as cross products whose magnitude is equal to the products of the magnitude of two vectors and sine of the angle between them and whose direction is perpendicular to the plane of the two vectors.

Mathematically it is written as 

 × = (AB sin θ)

Where θ is the angle between a vector  and  

EXPLANATION:

Mathematically it is written as 

 × = ABsinθ

If the vector is parallel then the angle between a vector  and  will be 0°

 ×  = ABsin0° = 0 (sin0° = 0)

If the vector is antiparallel then the angle between a vector  and  will be 180° 

 ×  = AB180° = 0 (sin180° = 0)

• So the Vector product of two parallel and anti-parallel vectors is a null vector.