tutor.eduforge
✦ Class 12 · Maths

Vectors

You'll see how a simple arrow can solve real‑world problems.

This lesson is not one of the free ones right now. Create a free account — it takes a few seconds, costs nothing, and opens 7 lessons plus your scores and doubts.

What this lesson covers

Step by step, in this order.

  1. 1A vector has magnitude and direction, drawn as an arrow.
  2. 2Magnitude is the size, measured in metres for displacement.
  3. 3A scalar has only magnitude, like temperature in degrees Celsius.
  4. 4A position vector joins the origin to a point in space.
  5. 5A unit vector has length one; for (1,2,2) it is (1/3,2/3,2/3).
  6. 6Vector addition uses tip‑to‑tail or the parallelogram law.
  7. 7Scaling a vector multiplies each component; 3·(2,‑1) = (6,‑3).
  8. 8Dot product a·b = |a||b|cosθ, gives work in joules.
  9. 9Cross product a×b = |a||b|sinθ n̂, gives torque in newton‑metre; Gibbs introduced it in 1880s.
  10. 10TRY IT: two forces 30 N at 60° – find resultant step by step.
The tutor's whiteboard, from a live lesson
How it looks

A real board, not a video.

This board is from a different Maths lesson — yours will look like this. She writes and draws while she explains, and stops to check you followed.

Doubts this lesson clears up

  • What does magnitude mean for a vector?
  • How do I find a unit vector from any vector?
  • Why does a zero dot product mean perpendicular?
  • How does the cross product give the area of a triangle?
  • What happens to a vector when multiplied by a negative number?
  • Can you give everyday examples of dot and cross products?

Give your child a better way to learn Maths & Science.

Interactive. NCERT-aligned. Any time, anywhere.

Start a free lesson →