Dot and Cross Product

Some of the common differences between dot and cross product of vectors are:

PropertyDot ProductCross Product
Definitiona⋅b = |a| |b| cos θ, where θ is the angle between the vectors.a×b = |a| |b| sin θ n̂, where θ is the angle between the vectors, and n̂ is a unit vector perpendicular to the plane containing a and b.
ResultScalarVector
CommutativityHolds [a⋅b = b⋅a]Doesn’t hold [a×b = −(b×a)]
DirectionScalar value, no directionPerpendicular to the plane containing a and b
OrthogonalityTwo vectors are orthogonal if their dot product is zero.The cross product of two non-zero vectors is orthogonal to both of them.
ApplicationsFinding the angle between vectors, projection of one vector onto anotherFinding torque in physics, determining normal vectors to surfaces

Read More,

Dot and Cross Products on Vectors

A quantity that is characterized not only by magnitude but also by its direction, is called a vector. Velocity, force, acceleration, momentum, etc. are vectors.  

Vectors can be multiplied in two ways:

  • Scalar product or Dot product
  • Vector Product or Cross product

Table of Content

  • Scalar Product/Dot Product of Vectors
    • Projection of one vector on other Vector
  • Properties of Scalar Product
  • Inequalities Based on Dot Product
  • Cross Product/Vector Product of Vectors
    • Properties of Cross Product
    • Cross product in Determinant Form
  • Dot and Cross Product
  • FAQs on Dot and Cross Products on Vectors

Similar Reads

Scalar Product/Dot Product of Vectors

The resultant scalar product/dot product of two vectors is always a scalar quantity. Consider two vectors a and b. The scalar product is calculated as the product of magnitudes of a, b, and cosine of the angle between these vectors....

Properties of Scalar Product

Scalar product of two vectors is always a real number (scalar).Scalar product is commutative i.e. a.b =b.a= |a||b| cos αIf α is 90° then Scalar product is zero as cos(90) = 0. So, the scalar product of unit vectors in x, y directions is 0.If α is 0° then the scalar product is the product of magnitudes of a and b |a||b|.Scalar product of a unit vector with itself is 1.Scalar product of a vector a with itself is |a|2If α is 1800, the scalar product for vectors a and b is -|a||b|Scalar product is distributive over addition...

Inequalities Based on Dot Product

There are various inequalities based on the dot product of vectors, such as:...

Examples of Dot Product of Vectors

Example 1. Consider two vectors such that |a|=6 and |b|=3 and α = 60°. Find their dot product....

Cross Product/Vector Product of Vectors

Readers are already familiar with a three-dimensional right-handed rectangular coordinate system. In this system, a counterclockwise rotation of the x-axis into the positive y-axis indicates that a right-handed (standard) screw would advance in the direction of the positive z-axis as shown in the figure....

Dot and Cross Product

Some of the common differences between dot and cross product of vectors are:...

FAQs on Dot and Cross Products on Vectors

What does the dot product represent geometrically?...