Question 51 of 68beginner🔧 ApplyShort Answer2 marks

Find the scalar components and magnitude of the vector joining the points P(x₁, y₁, z₁) and Q(x₂, y₂, z₂).

Correct Answer

The vector joining points P(x₁, y₁, z₁) and Q(x₂, y₂, z₂) is given by:

PQ = (x₂ - x₁)î + (y₂ - y₁)ĵ + (z₂ - z₁)k̂

The scalar components of this vector are (x₂ - x₁), (y₂ - y₁), and (z₂ - z₁).

The magnitude of the vector is:

|PQ| = √[(x₂ - x₁)² + (y₂ - y₁)² + (z₂ - z₁)²]

Exercise: MISCELLANEOUS EXERCISE ON CHAPTER 10 | Q: 2 | (Page 35)
For More Understanding

Explanation

The context clearly explains in section 10.5.2 that when we have two points P₁(x₁, y₁, z₁) and P₂(x₂, y₂, z₂), the vector joining them is obtained by subtracting the position vectors. The scalar components are the coefficients of î, ĵ, and k̂ in the component form. The magnitude formula follows from the distance formula between two points in 3D space.

Solution Steps

  1. Step 1: Write the position vectors of P and Q as OP = x₁î + y₁ĵ + z₁k̂ and OQ = x₂î + y₂ĵ + z₂k̂

  2. Step 2: Find the vector PQ = OQ - OP = (x₂ - x₁)î + (y₂ - y₁)ĵ + (z₂ - z₁)k̂

  3. Step 3: Identify scalar components as (x₂ - x₁), (y₂ - y₁), (z₂ - z₁)

  4. Step 4: Apply magnitude formula |PQ| = √[(x₂ - x₁)² + (y₂ - y₁)² + (z₂ - z₁)²]