Direction is part of the quantity
Speed is just a number. Velocity is a speed plus a direction. Two vectors of the same size pointing different ways are not the same vector.
Class 11 to 12 · 12 games
Vectors, explained with pictures
A quantity with both a size and a direction.
In everyday life: Wind at 20 km/h from the north, or a push to the left.
Magnitude comes from Pythagoras
A vector with parts 3 across and 4 up has magnitude 5, because the parts form a right triangle and the vector is its hypotenuse.
A worked example
What is the magnitude of the vector (6, 8)?
10
6 squared is 36, 8 squared is 64, and they add to 100. The square root of 100 is 10.
Words to know
- vector
- A quantity with a size and a direction.
- magnitude
- The size, or length, of a vector.
- component
- How far the vector goes along one axis.
In the games
You will match vectors to their magnitudes and compare which vector is longer.
Skills
- Magnitude of a vector · Class 12
- Add vectors and take a dot product · Class 12
- Points and lines in three dimensions · Class 12
By class
Class 11 vectors (3) · Class 12 vectors (9)
Practise vectors in Tivumo
No download, no account for your child. Classes 3 to 12, more than 1,000 games.