VECTORS

VECTORS

(a)       The physical quantities which have magnitude and direction and which can be added according to the triangle rule, are called vector quantities.

            Examples: force, linear momentum, electric field, magnetic field etc.

(b)       If a physical quantity has magnitude as well as direction but does not add up according to the triangle rule, it will not be called a vector quantity. 

            Example Electric current in a wire has both magnitude and direction but there is no any meaning of triangle rule. Thus, electric current is not a vector quantity.

1.1 Various types of vectors

 (a)   Polar Vectors:

 Vectors having the starting point (as in a case of displacement) or point of application (as in

the case of force) are polar vectors.

 (b)   Axial vectors

Vectors representing rotational effects and are always along the axis of rotation in accordance 

with right-hand screw rule are axial vectors.

Ex. Angular displacement (q); Angular velocity (w); Angular acceleration (a) ; Torque (t) etc.