Vectors - Projection of Vectors

  • Introduction to vectors and their properties
  • Understanding the concept of projection
  • Definition of projection of a vector onto another vector
  • Geometric interpretation of projection
  • Expression of the projection of vector ‘a’ onto vector ‘b’ as
    • Proj(a,b) = (a ยท b) / ||b||^2 * b
  • Example 1: Suppose vector a = 2i + 3j + k and vector b = i - j + 2k. Find the projection of vector a onto vector b.
  • Example 2: Determine the projection of vector a = 3i - 2j onto vector b = 4i + 5j.
  • Orthogonal projection and its properties
  • Calculation of orthogonal projection using dot product "
  1. Applications of Vector Projection
  • Vector projection in physics and engineering applications
  • Finding the component of a force in a specified direction
  • Calculating work done by a force along a given direction
  • Determining the magnitude and direction of a force needed to produce a desired effect
  • Example: A 15 kg crate is being pulled with a force of 100 N at an angle of 30 degrees with the horizontal. Find the horizontal and vertical components of the force.
  1. Vector Projection in Two Dimensions
  • Projection of a vector onto the x-axis and y-axis
  • Expressing a vector in terms of its components
  • Finding the magnitude and direction of the projection
  • Example: Consider vector u = 3i + 4j. Find the projections of u onto the x-axis and y-axis.
  1. Projection of a Vector onto a Plane
  • Introduction to projection of a vector onto a plane
  • Determining the projection of a vector onto a plane
  • Definition of the normal vector of a plane
  • Calculating the projection using dot product and normal vector
  • Example: Find the projection of vector v = 2i - j + 3k onto the plane with equation 2x + 3y - z = 4.
  1. Orthogonal Projection onto a Plane
  • Understanding orthogonal projection onto a plane
  • Definition and properties of orthogonal projection
  • Calculation of orthogonal projection using dot product and normal vector
  • Example: Determine the orthogonal projection of vector a = 4i + 2j - k onto the plane with equation 3x + 4y - 2z = 5.
  1. Vector Projection in Three Dimensions
  • Extending the concept of vector projection to three dimensions
  • Finding the projection of a vector onto a line in three dimensions
  • Determining the projection of a vector onto a plane in three dimensions
  • Example: Consider vector v = i - 2j - 3k. Find the projection of v onto the line with direction vector 2i + j - k.
  1. Scalar Projection
  • Introduction to scalar projection
  • Definition of scalar projection
  • Calculation of scalar projection using dot product
  • Example: Find the scalar projection of vector a = 3i + 4j onto the vector b = 2i - j.
  1. Vector Projection as a Linear Transformation
  • Relationship between vector projection and linear transformation
  • Understanding the transformation matrix for vector projection
  • Applying vector projection as a linear transformation
  • Example: Consider vectors u = 3i + 2j and v = 4i - j. Find the transformation matrix for the projection of u onto v.
  1. Properties of Vector Projection
  • Properties of vector projection
  • Commutative property: Proj(a, b) = Proj(b, a)
  • Distributive property: Proj(a, b + c) = Proj(a, b) + Proj(a, c)
  • Example: Prove the commutative and distributive properties of vector projection.
  1. Vector Projection and Vector Addition
  • Relationship between vector projection and vector addition
  • Expressing the sum of two vectors in terms of their projections
  • Example: Let a, b, and c be vectors. Show that a - Proj(a, b) = Proj(a, c), where c = b + (a - Proj(a, b)).
  1. Summary
  • Recap of key concepts covered in the lecture
  • Importance of understanding vector projection in various applications
  • Review of properties and calculations related to vector projection
  • Encouragement for further exploration and practice of vector projection

Vectors - Projection Of Vectors

Slide 21:

  • Recap of vector projection onto a plane in three dimensions
  • Example: Find the projection of vector v = i + j + k onto the plane with equation x - 2y + z = 5.

Slide 22:

  • Recap of scalar projection and its calculation using dot product
  • Example: Determine the scalar projection of vector a = 4i - 2j + 3k onto vector b = 3i + j - k.

Slide 23:

  • Vector projection as a linear transformation
  • Defining the transformation matrix for vector projection
  • Example: Let a = 2i + j and b = 3i - k. Find the transformation matrix for the projection of a onto b.

Slide 24:

  • Properties of vector projection: Normalization
  • Introduction to the concept of normalizing a vector
  • Normalizing a vector as a prerequisite for vector projection
  • Example: Normalize the vector v = 2i + 3j - k.

Slide 25:

  • Properties of vector projection: Zero vector
  • Understanding the case of projecting a zero vector onto another vector
  • Zero vector as the result of projecting a zero vector
  • Example: Find the projection of the zero vector onto vector b = i + 2j - k.

Slide 26:

  • Properties of vector projection: Magnitude relation
  • Relationship between the magnitude of the projection and the original vector
  • Magnitude of the projection as a fraction of the original vector
  • Example: Show that the magnitude of the projection of vector a onto vector b is less than or equal to the magnitude of vector a.

Slide 27:

  • Properties of vector projection: Orthogonality
  • Understanding the orthogonality of the projection and the difference vector
  • Difference vector as the component orthogonal to the projection
  • Example: Prove that the difference vector between a vector and its projection is orthogonal to the projection vector.

Slide 28:

  • Applications of vector projection in physics: Kinematics
  • Calculation of displacement, velocity, and acceleration components
  • Example: A particle moves with a velocity vector v = 4i - 2j - 3k. Determine its components parallel and perpendicular to the vector a = 2i + j.

Slide 29:

  • Applications of vector projection in physics: Work and Energy
  • Determining the work done by a force in a specified direction
  • Calculation of the component of a force along a given direction
  • Example: A force of 50 N makes an angle of 60 degrees with the vertical. Find the work done in lifting an object vertically through 10 m.

Slide 30:

  • Summary of the lecture
  • Key takeaways from the topic of vector projection
  • Importance of understanding vector projection in various fields
  • Encouragement for further practice and exploration of vector projection