1. Concepts of Vectors and scalars ,magnitude and direction of a vector

There are two types of physical quantities vector quantity and scalar quantity

Scalar quantity

The quantities which are the only magnitude are called scalar quantities for example time

Vector quantity

The physical quantities which have both direction and magnitude are called vector quantities for example velocity

How can we find the magnitude of a vector

Let A = 2i+3j+4k 

Magnitude of vector = ✓2²+3²+4²

                                    = ✓ 4+9+16 = ✓ 29 

Chapter 10

Concepts of Vectors and scalars ,magnitude and direction of a vector :

The Physical quantity is either a vector or a scalar. These two categories can be distinguished from one another by their distinct definitions:

 Scalars are Physical quantities that has magnitude but no particular direction is described as scalar. 

Vectors are Physical quantities that are fully described by both a magnitude and a direction and also satisfy the triangle law of vector addition.

Examples of Scalar Quantities                                             

Some examples of scalar include:

• Mass
• Speed
• Distance
• Time
• Area
• Volume
• Density
• Temperature

Examples of Vector Quantities

Examples of vector quantity include:

• Linear momentum
• Acceleration
• Displacement
• Momentum
• Angular velocity
• Force
• Electric field
• Polarization

Initial Points – The point A where from the vector starts is known as initial point.

Terminal Point – The point B, where it ends is said to be the terminal point.

Magnitude – The distance between initial point and terminal point of a vector is the

Position Vector – Consider a point p (x, y, z) in space. The vector with initial point, origin O and terminal point P, is called the position vector of P.